Buy & Sell 
The most fundamental transaction types: buying increases your holdings and decreases cash; selling does the reverse and realizes a profit or loss.
🔑 Key Properties
| Property | Buy | Sell |
|---|---|---|
| Code | BUY |
SELL |
| Cash effect | ⬇️ Decreases | ⬆️ Increases |
| Asset effect | ⬆️ Increases holdings | ⬇️ Decreases holdings |
| Tax event | No | Yes (realizes gain/loss) |
📊 How It Works
🛒 Buy
When you buy an asset, a lot is created with:
- Date: When the purchase occurred
- Quantity: Number of shares/units bought
- Unit price: Price per share at the time of purchase
- Fees: Any transaction fees (commission, spread, etc.)
- Total cost:
quantity × unit_price + fees
💰 Sell
When you sell, LibreFolio matches the sale against existing lots using FIFO (First In, First Out) to determine:
\[
\text{Capital Gain} = (P_{sell} \times Q) - (P_{buy} \times Q) - \text{Fees}
\]
FIFO Matching
LibreFolio computes lot matching at runtime — it's not persisted in the database. This allows for flexible what-if analysis and potential future support for other matching methods (LIFO, specific identification).
🔗 Related
- 📊 Weighted Average Cost (WAC) — Average cost per unit across multiple buys
- 🔬 FIFO Lot Analysis — Per-lot drill-down into the FIFO matching introduced above
- 💰 Taxation — Capital gains, matching methods, loss carry-forward
- 📈 Returns — Measuring investment performance