diff --git a/PERFORMANCE_ANALYSIS.md b/PERFORMANCE_ANALYSIS.md
new file mode 100644
index 0000000..ce457b3
--- /dev/null
+++ b/PERFORMANCE_ANALYSIS.md
@@ -0,0 +1,230 @@
+# Backend Performance-Analyse: Sell-Funktionen
+
+## Identifizierte Performance-Probleme
+
+### 1. **N+1 Query Problem in `sellAllProducts()`**
+
+**Problem:**
+Die Funktion `sellAllProducts()` macht für jedes Inventory-Item mehrere separate Datenbankabfragen:
+
+1. **Erste Schleife (Zeile 1702-1711):**
+   - `calcRegionalSellPrice()` → macht `TownProductWorth.findOne()` für jedes Item
+   - `getCumulativeTaxPercentWithExemptions()` → macht mehrere Queries pro Item:
+     - `FalukantCharacter.findOne()`
+     - `PoliticalOffice.findAll()` mit Includes
+     - Rekursive SQL-Query für Steuerberechnung
+   - `addSellItem()` → macht `Branch.findOne()` und `DaySell.findOne()`/`create()` für jedes Item
+
+2. **Zweite Schleife (Zeile 1714-1724):**
+   - `RegionData.findOne()` für jedes Item
+   - `getCumulativeTaxPercent()` → rekursive SQL-Query für jedes Item
+   - `calcRegionalSellPrice()` → erneut `TownProductWorth.findOne()` für jedes Item
+
+**Beispiel:** Bei 10 Items werden gemacht:
+- 10x `TownProductWorth.findOne()` (2x pro Item)
+- 10x `RegionData.findOne()`
+- 10x `getCumulativeTaxPercentWithExemptions()` (mit mehreren Queries)
+- 10x `getCumulativeTaxPercent()` (rekursive SQL)
+- 10x `addSellItem()` (mit 2 Queries pro Item)
+- = **~70+ Datenbankabfragen für 10 Items**
+
+### 2. **Ineffiziente `addSellItem()` Implementierung**
+
+**Problem:**
+- Wird für jedes Item einzeln aufgerufen
+- Macht `Branch.findOne()` für jedes Item (könnte gecacht werden)
+- `DaySell.findOne()` und `create()`/`update()` für jedes Item
+
+**Lösung:** Batch-Operation implementieren, die alle DaySell Einträge auf einmal verarbeitet.
+
+### 3. **Doppelte Berechnungen in `sellAllProducts()`**
+
+**Problem:**
+- Preis wird zweimal berechnet (Zeile 1705 und 1718)
+- Steuer wird zweimal berechnet (Zeile 1706 und 1717)
+- `calcRegionalSellPrice()` wird zweimal aufgerufen mit denselben Parametern
+
+### 4. **Fehlende Indizes**
+
+**Potenzielle fehlende Indizes:**
+- `falukant_data.town_product_worth(product_id, region_id)` - sollte unique sein
+- `falukant_data.inventory(stock_id, product_id, quality)` - für schnelle Lookups
+- `falukant_data.knowledge(character_id, product_id)` - für Knowledge-Lookups
+- `falukant_data.political_office(character_id)` - für Steuerbefreiungen
+
+### 5. **Ineffiziente `getCumulativeTaxPercentWithExemptions()`**
+
+**Problem:**
+- Lädt alle PoliticalOffices jedes Mal neu, auch wenn sich nichts geändert hat
+- Macht komplexe rekursive SQL-Query für jedes Item separat
+- Könnte gecacht werden (z.B. pro User+Region Kombination)
+
+## Empfohlene Optimierungen
+
+### 1. **Batch-Loading für `sellAllProducts()`**
+
+```javascript
+async sellAllProducts(hashedUserId, branchId) {
+    // ... existing code ...
+    
+    // Batch-Load alle benötigten Daten VOR den Schleifen
+    const regionIds = [...new Set(inventory.map(item => item.stock.branch.regionId))];
+    const productIds = [...new Set(inventory.map(item => item.productType.id))];
+    
+    // 1. Lade alle TownProductWorth Einträge auf einmal
+    const townWorths = await TownProductWorth.findAll({
+        where: {
+            productId: { [Op.in]: productIds },
+            regionId: { [Op.in]: regionIds }
+        }
+    });
+    const worthMap = new Map();
+    townWorths.forEach(tw => {
+        worthMap.set(`${tw.productId}-${tw.regionId}`, tw.worthPercent);
+    });
+    
+    // 2. Lade alle RegionData auf einmal
+    const regions = await RegionData.findAll({
+        where: { id: { [Op.in]: regionIds } }
+    });
+    const regionMap = new Map(regions.map(r => [r.id, r]));
+    
+    // 3. Berechne Steuern für alle Regionen auf einmal
+    const taxMap = new Map();
+    for (const regionId of regionIds) {
+        const tax = await getCumulativeTaxPercentWithExemptions(falukantUser.id, regionId);
+        taxMap.set(regionId, tax);
+    }
+    
+    // 4. Berechne Preise und Steuern in einer Schleife
+    const sellItems = [];
+    for (const item of inventory) {
+        const regionId = item.stock.branch.regionId;
+        const worthPercent = worthMap.get(`${item.productType.id}-${regionId}`) || 50;
+        const knowledgeVal = item.productType.knowledges[0]?.knowledge || 0;
+        const pricePerUnit = calcRegionalSellPrice(item.productType, knowledgeVal, regionId, worthPercent);
+        const cumulativeTax = taxMap.get(regionId);
+        // ... rest of calculation ...
+        sellItems.push({ branchId: item.stock.branch.id, productId: item.productType.id, quantity: item.quantity });
+    }
+    
+    // 5. Batch-Update DaySell Einträge
+    await this.addSellItemsBatch(sellItems);
+    
+    // ... rest of code ...
+}
+```
+
+### 2. **Batch-Operation für `addSellItem()`**
+
+```javascript
+async addSellItemsBatch(sellItems) {
+    // Gruppiere nach (regionId, productId, sellerId)
+    const grouped = new Map();
+    for (const item of sellItems) {
+        const branch = await Branch.findByPk(item.branchId);
+        if (!branch) continue;
+        
+        const key = `${branch.regionId}-${item.productId}-${item.sellerId}`;
+        if (!grouped.has(key)) {
+            grouped.set(key, {
+                regionId: branch.regionId,
+                productId: item.productId,
+                sellerId: item.sellerId,
+                quantity: 0
+            });
+        }
+        grouped.get(key).quantity += item.quantity;
+    }
+    
+    // Batch-Update oder Create
+    for (const [key, data] of grouped) {
+        const [daySell, created] = await DaySell.findOrCreate({
+            where: {
+                regionId: data.regionId,
+                productId: data.productId,
+                sellerId: data.sellerId
+            },
+            defaults: { quantity: data.quantity }
+        });
+        
+        if (!created) {
+            daySell.quantity += data.quantity;
+            await daySell.save();
+        }
+    }
+}
+```
+
+### 3. **Caching für `getCumulativeTaxPercentWithExemptions()`**
+
+```javascript
+// Cache für Steuerberechnungen (z.B. 5 Minuten)
+const taxCache = new Map();
+const CACHE_TTL = 5 * 60 * 1000; // 5 Minuten
+
+async function getCumulativeTaxPercentWithExemptions(userId, regionId) {
+    const cacheKey = `${userId}-${regionId}`;
+    const cached = taxCache.get(cacheKey);
+    if (cached && Date.now() - cached.timestamp < CACHE_TTL) {
+        return cached.value;
+    }
+    
+    // ... existing calculation ...
+    
+    taxCache.set(cacheKey, { value: tax, timestamp: Date.now() });
+    return tax;
+}
+```
+
+### 4. **Optimierte `calcRegionalSellPrice()`**
+
+```javascript
+async function calcRegionalSellPrice(product, knowledgeFactor, regionId, worthPercent = null) {
+    // Wenn worthPercent nicht übergeben wurde UND wir es nicht aus dem Cache haben,
+    // dann hole es aus der DB
+    if (worthPercent === null) {
+        const townWorth = await TownProductWorth.findOne({
+            where: { productId: product.id, regionId: regionId }
+        });
+        worthPercent = townWorth?.worthPercent || 50;
+    }
+    
+    // ... rest of calculation ...
+}
+```
+
+### 5. **Datenbank-Indizes hinzufügen**
+
+```sql
+-- Index für town_product_worth (sollte unique sein)
+CREATE UNIQUE INDEX IF NOT EXISTS idx_town_product_worth_product_region 
+ON falukant_data.town_product_worth(product_id, region_id);
+
+-- Index für inventory Lookups
+CREATE INDEX IF NOT EXISTS idx_inventory_stock_product_quality 
+ON falukant_data.inventory(stock_id, product_id, quality);
+
+-- Index für knowledge Lookups
+CREATE INDEX IF NOT EXISTS idx_knowledge_character_product 
+ON falukant_data.knowledge(character_id, product_id);
+
+-- Index für political_office Lookups
+CREATE INDEX IF NOT EXISTS idx_political_office_character 
+ON falukant_data.political_office(character_id);
+```
+
+## Geschätzter Performance-Gewinn
+
+- **Vorher:** ~70+ Queries für 10 Items
+- **Nachher:** ~15-20 Queries für 10 Items (Batch-Loading + Caching)
+- **Geschätzte Verbesserung:** 70-80% weniger Datenbankabfragen
+
+## Priorität
+
+1. **Hoch:** Batch-Loading für `sellAllProducts()` (größter Impact)
+2. **Hoch:** Batch-Operation für `addSellItem()`
+3. **Mittel:** Caching für Steuerberechnungen
+4. **Mittel:** Datenbank-Indizes
+5. **Niedrig:** Doppelte Berechnungen entfernen
+
diff --git a/SELL_OVERVIEW.md b/SELL_OVERVIEW.md
new file mode 100644
index 0000000..2c63908
--- /dev/null
+++ b/SELL_OVERVIEW.md
@@ -0,0 +1,601 @@
+# Übersicht: Sell-Funktionen und verwendete Models/Tabellen
+
+## Sell-Funktionen in `falukantService.js`
+
+### 1. `sellProduct(hashedUserId, branchId, productId, quality, quantity)`
+Verkauft ein einzelnes Produkt mit bestimmter Qualität.
+
+**Ablauf:**
+1. Lädt User, Branch, Character, Stock
+2. Lädt Inventory mit ProductType und Knowledge
+3. Berechnet Preis pro Einheit mit `calcRegionalSellPrice()`
+4. Berechnet kumulative Steuer mit politischen Befreiungen
+5. Passt Preis an (Inflation basierend auf Steuer)
+6. Berechnet Revenue, Tax, Net
+7. Aktualisiert Geld für Verkäufer und Treasury
+8. Entfernt verkaufte Items aus Inventory
+9. Erstellt/aktualisiert DaySell Eintrag
+10. Sendet Socket-Notifications
+
+**Verwendete Models/Tabellen:**
+- `FalukantUser` (`falukant_data.falukant_user`)
+- `Branch` (`falukant_data.branch`)
+- `FalukantCharacter` (`falukant_data.character`)
+- `FalukantStock` (`falukant_data.stock`)
+- `Inventory` (`falukant_data.inventory`)
+- `ProductType` (`falukant_type.product`)
+- `Knowledge` (`falukant_data.knowledge`)
+- `TownProductWorth` (`falukant_data.town_product_worth`)
+- `RegionData` (`falukant_data.region`)
+- `RegionType` (`falukant_type.region`)
+- `PoliticalOffice` (`falukant_data.political_office`)
+- `PoliticalOfficeType` (`falukant_type.political_office_type`)
+- `DaySell` (`falukant_log.day_sell`)
+- `MoneyFlow` (via `updateFalukantUserMoney`)
+
+### 2. `sellAllProducts(hashedUserId, branchId)`
+Verkauft alle Produkte eines Branches.
+
+**Ablauf:**
+1. Lädt User, Branch mit Stocks
+2. Lädt alle Inventory Items mit ProductType, Knowledge, Stock, Branch
+3. Für jedes Item:
+   - Berechnet Preis pro Einheit
+   - Berechnet kumulative Steuer
+   - Passt Preis an
+   - Erstellt/aktualisiert DaySell Eintrag
+4. Berechnet Gesamt-Tax pro Region
+5. Aktualisiert Geld für Verkäufer und Treasury
+6. Löscht alle Inventory Items
+7. Sendet Socket-Notifications
+
+**Verwendete Models/Tabellen:**
+- `FalukantUser` (`falukant_data.falukant_user`)
+- `Branch` (`falukant_data.branch`)
+- `FalukantStock` (`falukant_data.stock`)
+- `FalukantStockType` (`falukant_type.stock`)
+- `FalukantCharacter` (`falukant_data.character`)
+- `Inventory` (`falukant_data.inventory`)
+- `ProductType` (`falukant_type.product`)
+- `Knowledge` (`falukant_data.knowledge`)
+- `TownProductWorth` (`falukant_data.town_product_worth`)
+- `RegionData` (`falukant_data.region`)
+- `RegionType` (`falukant_type.region`)
+- `PoliticalOffice` (`falukant_data.political_office`)
+- `PoliticalOfficeType` (`falukant_type.political_office_type`)
+- `DaySell` (`falukant_log.day_sell`)
+- `MoneyFlow` (via `updateFalukantUserMoney`)
+
+### 3. `addSellItem(branchId, userId, productId, quantity)`
+Erstellt oder aktualisiert einen DaySell Eintrag für einen Verkauf.
+
+**Ablauf:**
+1. Lädt Branch
+2. Sucht nach existierendem DaySell Eintrag
+3. Erstellt neuen oder aktualisiert existierenden Eintrag
+
+**Verwendete Models/Tabellen:**
+- `Branch` (`falukant_data.branch`)
+- `DaySell` (`falukant_log.day_sell`)
+
+## Hilfsfunktionen
+
+### `calcRegionalSellPrice(product, knowledgeFactor, regionId, worthPercent = null)`
+Berechnet den Verkaufspreis eines Produkts basierend auf:
+- Basispreis (`product.sellCost`)
+- Regionalem Worth-Percent (`town_product_worth.worth_percent`)
+- Knowledge-Faktor (0-100)
+
+**Verwendete Models/Tabellen:**
+- `ProductType` (`falukant_type.product`)
+- `TownProductWorth` (`falukant_data.town_product_worth`)
+
+### `getCumulativeTaxPercent(regionId)`
+Berechnet die kumulative Steuer für eine Region und alle Vorfahren (rekursiv).
+
+**SQL Query:**
+```sql
+WITH RECURSIVE ancestors AS (
+    SELECT id, parent_id, tax_percent
+    FROM falukant_data.region r
+    WHERE id = :id
+  UNION ALL
+    SELECT reg.id, reg.parent_id, reg.tax_percent
+    FROM falukant_data.region reg
+    JOIN ancestors a ON reg.id = a.parent_id
+)
+SELECT COALESCE(SUM(tax_percent),0) AS total FROM ancestors;
+```
+
+**Verwendete Tabellen:**
+- `falukant_data.region`
+
+### `getCumulativeTaxPercentWithExemptions(userId, regionId)`
+Berechnet die kumulative Steuer mit politischen Befreiungen.
+
+**Ablauf:**
+1. Lädt Character des Users
+2. Lädt alle PoliticalOffices des Characters
+3. Bestimmt befreite Region-Typen basierend auf Ämtern
+4. Berechnet kumulative Steuer, aber schließt befreite Region-Typen aus
+
+**SQL Query:**
+```sql
+WITH RECURSIVE ancestors AS (
+    SELECT r.id, r.parent_id, r.tax_percent, rt.label_tr as region_type
+    FROM falukant_data.region r
+    JOIN falukant_type.region rt ON rt.id = r.region_type_id
+    WHERE r.id = :id
+  UNION ALL
+    SELECT reg.id, reg.parent_id, reg.tax_percent, rt2.label_tr
+    FROM falukant_data.region reg
+    JOIN falukant_type.region rt2 ON rt2.id = reg.region_type_id
+    JOIN ancestors a ON reg.id = a.parent_id
+)
+SELECT COALESCE(SUM(CASE WHEN ARRAY[...] && ARRAY[region_type]::text[] THEN 0 ELSE tax_percent END),0) AS total FROM ancestors;
+```
+
+**Verwendete Models/Tabellen:**
+- `FalukantCharacter` (`falukant_data.character`)
+- `PoliticalOffice` (`falukant_data.political_office`)
+- `PoliticalOfficeType` (`falukant_type.political_office_type`)
+- `RegionData` (`falukant_data.region`)
+- `RegionType` (`falukant_type.region`)
+
+**Politische Steuerbefreiungen:**
+```javascript
+const POLITICAL_TAX_EXEMPTIONS = {
+    'council': ['city'],
+    'taxman': ['city', 'county'],
+    'treasurerer': ['city', 'county', 'shire'],
+    'super-state-administrator': ['city', 'county', 'shire', 'markgrave', 'duchy'],
+    'chancellor': ['city','county','shire','markgrave','duchy'] // = alle Typen
+};
+```
+
+## Model-Definitionen
+
+### Inventory (`falukant_data.inventory`)
+```javascript
+// backend/models/falukant/data/inventory.js
+- id
+- stockId (FK zu falukant_data.stock)
+- productId (FK zu falukant_type.product)
+- quantity
+- quality
+- producedAt
+```
+
+### DaySell (`falukant_log.day_sell`)
+```javascript
+// backend/models/falukant/log/daysell.js
+- id
+- regionId (FK zu falukant_data.region)
+- productId (FK zu falukant_type.product)
+- sellerId (FK zu falukant_data.falukant_user)
+- quantity
+- createdAt
+- updatedAt
+```
+
+### TownProductWorth (`falukant_data.town_product_worth`)
+```javascript
+// backend/models/falukant/data/town_product_worth.js
+- id
+- productId (FK zu falukant_type.product)
+- regionId (FK zu falukant_data.region)
+- worthPercent (0-100)
+```
+
+### Knowledge (`falukant_data.knowledge`)
+```javascript
+// backend/models/falukant/data/product_knowledge.js
+- id
+- productId (FK zu falukant_type.product)
+- characterId (FK zu falukant_data.character)
+- knowledge (0-99)
+```
+
+## Wichtige SQL-Queries
+
+### 1. Inventory mit ProductType und Knowledge laden
+```javascript
+Inventory.findAll({
+    where: { quality },
+    include: [
+        {
+            model: ProductType,
+            as: 'productType',
+            required: true,
+            where: { id: productId },
+            include: [
+                {
+                    model: Knowledge,
+                    as: 'knowledges',
+                    required: false,
+                    where: { characterId: character.id }
+                }
+            ]
+        }
+    ]
+})
+```
+
+### 2. Kumulative Steuer mit Befreiungen berechnen
+Siehe `getCumulativeTaxPercentWithExemptions()` oben.
+
+## Preisberechnung
+
+### Formel für `calcRegionalSellPrice`:
+1. Basispreis = `product.sellCost * (worthPercent / 100)`
+2. Min = `basePrice * 0.6`
+3. Max = `basePrice`
+4. Preis = `min + (max - min) * (knowledgeFactor / 100)`
+
+### Steueranpassung:
+1. `inflationFactor = cumulativeTax >= 100 ? 1 : (1 / (1 - cumulativeTax / 100))`
+2. `adjustedPricePerUnit = pricePerUnit * inflationFactor`
+3. `revenue = quantity * adjustedPricePerUnit`
+4. `taxValue = revenue * cumulativeTax / 100`
+5. `net = revenue - taxValue`
+
+## Vollständige Code-Snippets
+
+### `calcRegionalSellPrice()`
+```javascript
+async function calcRegionalSellPrice(product, knowledgeFactor, regionId, worthPercent = null) {
+    if (worthPercent === null) {
+        const townWorth = await TownProductWorth.findOne({
+            where: { productId: product.id, regionId: regionId }
+        });
+        worthPercent = townWorth?.worthPercent || 50; // Default 50% wenn nicht gefunden
+    }
+    
+    // Basispreis basierend auf regionalem worthPercent
+    const basePrice = product.sellCost * (worthPercent / 100);
+    
+    // Dann Knowledge-Faktor anwenden
+    const min = basePrice * 0.6;
+    const max = basePrice;
+    return min + (max - min) * (knowledgeFactor / 100);
+}
+```
+
+### `getCumulativeTaxPercent()`
+```javascript
+async function getCumulativeTaxPercent(regionId) {
+    if (!regionId) return 0;
+    const rows = await sequelize.query(
+        `WITH RECURSIVE ancestors AS (
+            SELECT id, parent_id, tax_percent
+            FROM falukant_data.region r
+            WHERE id = :id
+          UNION ALL
+            SELECT reg.id, reg.parent_id, reg.tax_percent
+            FROM falukant_data.region reg
+            JOIN ancestors a ON reg.id = a.parent_id
+        )
+        SELECT COALESCE(SUM(tax_percent),0) AS total FROM ancestors;`,
+        {
+            replacements: { id: regionId },
+            type: sequelize.QueryTypes.SELECT
+        }
+    );
+    const val = rows?.[0]?.total ?? 0;
+    return parseFloat(val) || 0;
+}
+```
+
+### `getCumulativeTaxPercentWithExemptions()` (vereinfacht)
+```javascript
+async function getCumulativeTaxPercentWithExemptions(userId, regionId) {
+    if (!regionId) return 0;
+    
+    // Character finden
+    const character = await FalukantCharacter.findOne({
+        where: { userId },
+        attributes: ['id']
+    });
+    if (!character) return 0;
+    
+    // Politische Ämter laden
+    const offices = await PoliticalOffice.findAll({
+        where: { characterId: character.id },
+        include: [
+            { model: PoliticalOfficeType, as: 'type', attributes: ['name'] },
+            {
+                model: RegionData,
+                as: 'region',
+                include: [{
+                    model: RegionType,
+                    as: 'regionType',
+                    attributes: ['labelTr']
+                }]
+            }
+        ]
+    });
+
+    // Befreite Region-Typen bestimmen
+    const exemptTypes = new Set();
+    let hasChancellor = false;
+    for (const o of offices) {
+        const name = o.type?.name;
+        if (!name) continue;
+        if (name === 'chancellor') { hasChancellor = true; break; }
+        const allowed = POLITICAL_TAX_EXEMPTIONS[name];
+        if (allowed && Array.isArray(allowed)) {
+            for (const t of allowed) exemptTypes.add(t);
+        }
+    }
+
+    if (hasChancellor) return 0;
+
+    // SQL Query mit Befreiungen
+    const exemptTypesArray = Array.from(exemptTypes);
+    const exemptTypesString = exemptTypesArray.length > 0 
+        ? `ARRAY[${exemptTypesArray.map(t => `'${t.replace(/'/g, "''")}'`).join(',')}]`
+        : `ARRAY[]::text[]`;
+    
+    const rows = await sequelize.query(
+        `WITH RECURSIVE ancestors AS (
+            SELECT r.id, r.parent_id, r.tax_percent, rt.label_tr as region_type
+            FROM falukant_data.region r
+            JOIN falukant_type.region rt ON rt.id = r.region_type_id
+            WHERE r.id = :id
+          UNION ALL
+            SELECT reg.id, reg.parent_id, reg.tax_percent, rt2.label_tr
+            FROM falukant_data.region reg
+            JOIN falukant_type.region rt2 ON rt2.id = reg.region_type_id
+            JOIN ancestors a ON reg.id = a.parent_id
+        )
+        SELECT COALESCE(SUM(CASE WHEN ${exemptTypesString} && ARRAY[region_type]::text[] THEN 0 ELSE tax_percent END),0) AS total FROM ancestors;`,
+        {
+            replacements: { id: regionId },
+            type: sequelize.QueryTypes.SELECT
+        }
+    );
+    const val = rows?.[0]?.total ?? 0;
+    return parseFloat(val) || 0;
+}
+```
+
+### `sellProduct()` (Kern-Logik)
+```javascript
+async sellProduct(hashedUserId, branchId, productId, quality, quantity) {
+    const user = await getFalukantUserOrFail(hashedUserId);
+    const branch = await getBranchOrFail(user.id, branchId);
+    const character = await FalukantCharacter.findOne({ where: { userId: user.id } });
+    if (!character) throw new Error('No character found for user');
+    const stock = await FalukantStock.findOne({ where: { branchId: branch.id } });
+    if (!stock) throw new Error('Stock not found');
+    
+    // Inventory laden
+    const inventory = await Inventory.findAll({
+        where: { quality },
+        include: [
+            {
+                model: ProductType,
+                as: 'productType',
+                required: true,
+                where: { id: productId },
+                include: [
+                    {
+                        model: Knowledge,
+                        as: 'knowledges',
+                        required: false,
+                        where: { characterId: character.id }
+                    }
+                ]
+            }
+        ]
+    });
+    if (!inventory.length) throw new Error('No inventory found');
+    
+    const available = inventory.reduce((sum, i) => sum + i.quantity, 0);
+    if (available < quantity) throw new Error('Not enough inventory available');
+    
+    const item = inventory[0].productType;
+    const knowledgeVal = item.knowledges?.[0]?.knowledge || 0;
+    const pricePerUnit = await calcRegionalSellPrice(item, knowledgeVal, branch.regionId);
+
+    // Steuer berechnen
+    const cumulativeTax = await getCumulativeTaxPercentWithExemptions(user.id, branch.regionId);
+    const inflationFactor = cumulativeTax >= 100 ? 1 : (1 / (1 - cumulativeTax / 100));
+    const adjustedPricePerUnit = Math.round(pricePerUnit * inflationFactor * 100) / 100;
+    const revenue = quantity * adjustedPricePerUnit;
+
+    // Tax und Net berechnen
+    const taxValue = Math.round((revenue * cumulativeTax / 100) * 100) / 100;
+    const net = Math.round((revenue - taxValue) * 100) / 100;
+
+    // Geld aktualisieren
+    const moneyResult = await updateFalukantUserMoney(user.id, net, `Product sale (net)`, user.id);
+    if (!moneyResult.success) throw new Error('Failed to update money for seller');
+
+    // Steuer an Treasury buchen
+    const treasuryId = process.env.TREASURY_FALUKANT_USER_ID;
+    if (treasuryId && taxValue > 0) {
+        const taxResult = await updateFalukantUserMoney(parseInt(treasuryId, 10), taxValue, `Sales tax (${cumulativeTax}%)`, user.id);
+        if (!taxResult.success) throw new Error('Failed to update money for treasury');
+    }
+    
+    // Inventory aktualisieren
+    let remaining = quantity;
+    for (const inv of inventory) {
+        if (inv.quantity <= remaining) {
+            remaining -= inv.quantity;
+            await inv.destroy();
+        } else {
+            await inv.update({ quantity: inv.quantity - remaining });
+            remaining = 0;
+            break;
+        }
+    }
+    
+    // DaySell Eintrag erstellen/aktualisieren
+    await this.addSellItem(branchId, user.id, productId, quantity);
+    
+    // Notifications senden
+    notifyUser(user.user.hashedId, 'falukantUpdateStatus', {});
+    notifyUser(user.user.hashedId, 'falukantBranchUpdate', { branchId: branch.id });
+    return { success: true };
+}
+```
+
+### `addSellItem()`
+```javascript
+async addSellItem(branchId, userId, productId, quantity) {
+    const branch = await Branch.findOne({
+        where: { id: branchId },
+    });
+    const daySell = await DaySell.findOne({
+        where: {
+            regionId: branch.regionId,
+            productId: productId,
+            sellerId: userId,
+        }
+    });
+    if (daySell) {
+        daySell.quantity += quantity;
+        await daySell.save();
+    } else {
+        await DaySell.create({
+            regionId: branch.regionId,
+            productId: productId,
+            sellerId: userId,
+            quantity: quantity,
+        });
+    }
+}
+```
+
+## Wichtige Hinweise
+
+1. **Inventory wird nach Verkauf gelöscht/aktualisiert**: Items werden aus der Inventory entfernt oder die Menge reduziert.
+
+2. **DaySell wird aggregiert**: Wenn bereits ein DaySell Eintrag für Region/Product/Seller existiert, wird die Menge addiert.
+
+3. **Steuer wird an Treasury gebucht**: Wenn `TREASURY_FALUKANT_USER_ID` gesetzt ist, wird die Steuer an diesen User gebucht.
+
+4. **Socket-Notifications**: Nach jedem Verkauf werden `falukantUpdateStatus` und `falukantBranchUpdate` Events gesendet.
+
+5. **Politische Befreiungen**: Bestimmte politische Ämter befreien von Steuern in bestimmten Region-Typen. Chancellor befreit von allen Steuern.
+
+6. **Preis-Inflation**: Der Preis wird basierend auf der Steuer inflatiert, damit der Netto-Betrag für den Verkäufer gleich bleibt.
+
+## Tabellenübersicht
+
+### `falukant_data.inventory`
+- `id` (PK)
+- `stock_id` (FK zu `falukant_data.stock`)
+- `product_id` (FK zu `falukant_type.product`)
+- `quantity` (INTEGER)
+- `quality` (INTEGER)
+- `produced_at` (DATE)
+
+### `falukant_log.sell` (DaySell)
+- `id` (PK)
+- `region_id` (FK zu `falukant_data.region`)
+- `product_id` (FK zu `falukant_type.product`)
+- `seller_id` (FK zu `falukant_data.falukant_user`)
+- `quantity` (INTEGER)
+- `sell_timestamp` (DATE)
+- **Unique Index**: `(seller_id, product_id, region_id)`
+
+### `falukant_data.town_product_worth`
+- `id` (PK)
+- `product_id` (FK zu `falukant_type.product`)
+- `region_id` (FK zu `falukant_data.region`)
+- `worth_percent` (INTEGER, 0-100)
+
+### `falukant_data.knowledge`
+- `id` (PK)
+- `product_id` (FK zu `falukant_type.product`)
+- `character_id` (FK zu `falukant_data.character`)
+- `knowledge` (INTEGER, 0-99)
+
+### `falukant_data.political_office`
+- `id` (PK)
+- `office_type_id` (FK zu `falukant_type.political_office_type`)
+- `character_id` (FK zu `falukant_data.character`)
+- `region_id` (FK zu `falukant_data.region`)
+- `created_at`, `updated_at`
+
+### `falukant_type.political_office_type`
+- `id` (PK)
+- `name` (STRING) - z.B. 'council', 'taxman', 'treasurerer', 'super-state-administrator', 'chancellor'
+- `seats_per_region` (INTEGER)
+- `region_type` (STRING)
+- `term_length` (INTEGER)
+
+### `falukant_data.region`
+- `id` (PK)
+- `name` (STRING)
+- `region_type_id` (FK zu `falukant_type.region`)
+- `parent_id` (FK zu `falukant_data.region`, nullable)
+- `map` (JSONB)
+- `tax_percent` (DECIMAL)
+
+### `falukant_type.region`
+- `id` (PK)
+- `label_tr` (STRING) - z.B. 'city', 'county', 'shire', 'markgrave', 'duchy'
+- `parent_id` (FK zu `falukant_type.region`, nullable)
+
+### `falukant_data.falukant_user`
+- `id` (PK)
+- `user_id` (FK zu `community.user`)
+- `money` (DECIMAL)
+- `credit_amount`, `today_credit_taken`, `credit_interest_rate`
+- `certificate`
+- `main_branch_region_id`
+- `last_nobility_advance_at`
+- `created_at`, `updated_at`
+
+### `falukant_data.character`
+- `id` (PK)
+- `user_id` (FK zu `falukant_data.falukant_user`)
+- `region_id` (FK zu `falukant_data.region`)
+- `first_name`, `last_name`
+- `birthdate`, `gender`, `health`
+- `title_of_nobility` (FK zu `falukant_type.title_of_nobility`)
+- `mood_id` (FK zu `falukant_type.mood`)
+- `created_at`, `updated_at`
+
+### `falukant_data.branch`
+- `id` (PK)
+- `branch_type_id` (FK zu `falukant_type.branch`)
+- `region_id` (FK zu `falukant_data.region`)
+- `falukant_user_id` (FK zu `falukant_data.falukant_user`)
+
+### `falukant_data.stock`
+- `id` (PK)
+- `branch_id` (FK zu `falukant_data.branch`)
+- `stock_type_id` (FK zu `falukant_type.stock`)
+- `quantity` (INTEGER)
+- `product_quality` (INTEGER, nullable)
+
+### `falukant_type.product`
+- `id` (PK)
+- `label_tr` (STRING, unique)
+- `category` (INTEGER)
+- `production_time` (INTEGER)
+- `sell_cost` (INTEGER)
+
+## Dateipfade
+
+- **Service**: `backend/services/falukantService.js`
+- **Models**:
+  - `backend/models/falukant/data/inventory.js`
+  - `backend/models/falukant/log/daysell.js`
+  - `backend/models/falukant/data/town_product_worth.js`
+  - `backend/models/falukant/data/product_knowledge.js`
+  - `backend/models/falukant/data/political_office.js`
+  - `backend/models/falukant/type/political_office_type.js`
+  - `backend/models/falukant/data/region.js`
+  - `backend/models/falukant/type/region.js`
+  - `backend/models/falukant/data/character.js`
+  - `backend/models/falukant/data/user.js`
+  - `backend/models/falukant/data/branch.js`
+  - `backend/models/falukant/data/stock.js`
+  - `backend/models/falukant/type/product.js`
+
diff --git a/frontend/src/components/falukant/SaleSection.vue b/frontend/src/components/falukant/SaleSection.vue
index c481234..256575a 100644
--- a/frontend/src/components/falukant/SaleSection.vue
+++ b/frontend/src/components/falukant/SaleSection.vue
@@ -20,8 +20,10 @@
               <td>{{ item.quality }}</td>
               <td>{{ item.totalQuantity }}</td>
               <td>
-                <input type="number" v-model.number="item.sellQuantity" :min="1" :max="item.totalQuantity" />
-                <button @click="sellItem(index)">{{ $t('falukant.branch.sale.sellButton') }}</button>
+                <input type="number" v-model.number="item.sellQuantity" :min="1" :max="item.totalQuantity" :disabled="sellingItemIndex === index" />
+                <button @click="sellItem(index)" :disabled="sellingItemIndex === index || sellingAll">
+                  {{ sellingItemIndex === index ? $t('falukant.branch.sale.selling') : $t('falukant.branch.sale.sellButton') }}
+                </button>
               </td>
               <td>
                 <div v-if="item.betterPrices && item.betterPrices.length > 0" class="price-cities">
@@ -36,7 +38,12 @@
             </tr>
           </tbody>
         </table>
-        <button @click="sellAll">{{ $t('falukant.branch.sale.sellAllButton') }}</button>
+        <button @click="sellAll" :disabled="sellingAll || sellingItemIndex !== null">
+          {{ sellingAll ? $t('falukant.branch.sale.selling') : $t('falukant.branch.sale.sellAllButton') }}
+        </button>
+        <div v-if="sellAllStatus" class="sell-all-status" :class="sellAllStatus.type">
+          {{ sellAllStatus.message }}
+        </div>
       </div>
       <div v-else>
         <p>{{ $t('falukant.branch.sale.noInventory') }}</p>
@@ -183,6 +190,9 @@
     data() {
       return {
         inventory: [],
+        sellingItemIndex: null,
+        sellingAll: false,
+        sellAllStatus: null,
         transportForm: {
           sourceKey: null,
           vehicleTypeId: null,
@@ -320,23 +330,55 @@
           maximumFractionDigits: 2,
         }).format(price);
       },
-      sellItem(index) {
+      async sellItem(index) {
+        if (this.sellingItemIndex !== null || this.sellingAll) return;
+        
         const item = this.inventory[index];
         const quantityToSell = item.sellQuantity || item.totalQuantity;
-        apiClient.post(`/api/falukant/sell`, {
-          branchId: this.branchId,
-          productId: item.product.id,
-          quantity: quantityToSell,
-          quality: item.quality,
-        }).catch(() => {
+        this.sellingItemIndex = index;
+        
+        try {
+          await apiClient.post(`/api/falukant/sell`, {
+            branchId: this.branchId,
+            productId: item.product.id,
+            quantity: quantityToSell,
+            quality: item.quality,
+          });
+          // Inventory neu laden nach erfolgreichem Verkauf
+          await this.loadInventory();
+        } catch (error) {
           alert(this.$t('falukant.branch.sale.sellError'));
-        });
+        } finally {
+          this.sellingItemIndex = null;
+        }
       },
-      sellAll() {
-        apiClient.post(`/api/falukant/sell/all`, { branchId: this.branchId })
-        .catch(() => {
-          alert(this.$t('falukant.branch.sale.sellAllError'));
-        });
+      async sellAll() {
+        if (this.sellingAll || this.sellingItemIndex !== null) return;
+        
+        this.sellingAll = true;
+        this.sellAllStatus = null;
+        
+        try {
+          const response = await apiClient.post(`/api/falukant/sell/all`, { branchId: this.branchId });
+          const revenue = response.data?.revenue || 0;
+          this.sellAllStatus = {
+            type: 'success',
+            message: this.$t('falukant.branch.sale.sellAllSuccess', { revenue: this.formatMoney(revenue) })
+          };
+          // Inventory neu laden nach erfolgreichem Verkauf
+          await this.loadInventory();
+        } catch (error) {
+          this.sellAllStatus = {
+            type: 'error',
+            message: this.$t('falukant.branch.sale.sellAllError')
+          };
+        } finally {
+          this.sellingAll = false;
+          // Status nach 5 Sekunden löschen
+          setTimeout(() => {
+            this.sellAllStatus = null;
+          }, 5000);
+        }
       },
       inventoryOptions() {
         return this.inventory.map((item, index) => ({
@@ -590,5 +632,20 @@
     color: #999;
     font-style: italic;
   }
+  .sell-all-status {
+    margin-top: 10px;
+    padding: 8px;
+    border-radius: 4px;
+  }
+  .sell-all-status.success {
+    background-color: #d4edda;
+    color: #155724;
+    border: 1px solid #c3e6cb;
+  }
+  .sell-all-status.error {
+    background-color: #f8d7da;
+    color: #721c24;
+    border: 1px solid #f5c6cb;
+  }
   </style>
   
\ No newline at end of file
diff --git a/frontend/src/i18n/locales/de/falukant.json b/frontend/src/i18n/locales/de/falukant.json
index e6d532a..a809d42 100644
--- a/frontend/src/i18n/locales/de/falukant.json
+++ b/frontend/src/i18n/locales/de/falukant.json
@@ -260,6 +260,10 @@
                 "sell": "Verkauf",
                 "sellButton": "Verkaufen",
                 "sellAllButton": "Alles verkaufen",
+                "selling": "Verkauf läuft...",
+                "sellError": "Fehler beim Verkauf des Produkts.",
+                "sellAllError": "Fehler beim Verkauf aller Produkte.",
+                "sellAllSuccess": "Alle Produkte wurden erfolgreich verkauft. Einnahmen: {revenue}"
                 "transportTitle": "Transport anlegen",
                 "transportSource": "Artikel",
                 "transportSourcePlaceholder": "Artikel wählen",