In 'Settings/Users/Access management', enable the right : 'Display the Return/exchange button on closed sales'.
Locate the initial sale from which the product is returned.
Click on the 'Return/Exchange' button.
In front of each product, you will find an 'Exchange' button to generate a credit note.
If the product returned is tracked into inventory, it will be automatically returned into inventory.
The credit note has a single ID number (single use) and you can print it as a barcode. The credit note has the negative price of the product returned and the same tax rate.
Consult pending credit notes in 'Reports/Pending credit notes'.
Create a new sale (= exchange sale), and add the replacement products.
Add the credit notes generated after the return:
If the amount of the exchange sale is positive, charge your customer with the remaining amount to pay and close the sale.
If the amount of the exchange sale is negative (the value of the credit note is higher than the total prices of replacement products), refund your customer or :
First, you need to create a 'Credit' product as an open-price product (the product price is set when you add it to the sale – more information).
Add this 'Credit' product to the exchange sale in order to balance the total amount at 0, and close the exchange sale with your default payment type. Then, proceed immediately to an exchange on the 'Credit' product of the sale to generate a new credit note for the remaining credit amount.
The Store Credit feature must be activated on your account (more information).
Validate the exchange sale with the CRED payment method.
The remaining credit amount is added to your customer store credit account. He can use it for a future purchase.