Do you have preset trade-in values for certain products but the customer doesn't always have a trade-in when they order the product? 


You can maintain two adjustment schedules where one excludes the trade-in allowance and the other includes the trade-in allowance. When an order is entered for an item that is eligible for a trade-in allowance, the schedule that excludes the trade-in allowance will default in, but if the sales person entering the order determines the client has a trade-in, they can change the adjustment schedule that defaults on the line to pull in the trade-in allowance.


Review the our knowledge document How to Retrieve a Trade-in Allowance Using a Second Adjustment Schedule (Doc ID 2061768.1) for the setup and processing of the two allowances.