The Marketing application has a commercial role, not an accounting one: it gives the customer the benefit and records it on the receipt. Stock records are managed separately, through Inventory.
Product offered through a Bonus promotion
The bonus product appears on the receipt with a zero value. The raw material consumption is deducted based on the product recipe, just like for any other sale.
If the product does not have a recipe, or if you gave the product from stock without recording it on the receipt, use a Consumption Receipt:
Inventory → Consumption Receipt → add the quantity → save.
The stock is deducted based on the date on the document.
100% discount or complimentary consumption
100% discount — the receipt is issued with a zero value for the respective product; the sale remains recorded with a total discount.
Complimentary consumption — the amount is deducted from the user's complimentary consumption allowance and tracked separately per employee.
Choose the option based on what you want to track: if you need tracking by employee, use Complimentary consumption.
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