Field help (PNHGROPRI) 

This field is used to determine the unit price of the product. This price is expressed in the return unit. When the principal information for the line necessary for the determination of a price list is entered, a price list search process is automatically carried out.
The objective of this search is to recover:

If the price list search does not yield any relevant result, the PURPRICE - default price list standard cost parameter (ACH chapter, PRI group) is set to 'Yes' for the return site company, the standard cost will be used to value the gross price (if it has been defined for the product). When the entered price is null, a message is displayed requesting confirmation from the user. From this field, click the Actions icon to:

When the return arises from a receipt, the gross price and the discounts are initialized by the prices and discounts of the receipt line and they are not accessible. This information will be used during the creation of a supplier credit memo to value said credit memo.