The scenario is : you have created a trade agreement for Product A with 4 Purchase price :
Case 1 : Purchase price 20 with find next checkbox is ticked and date range between November 20 to December 31.
Case 2 : Purchase price 12 with find next checkbox is ticked and date range between November 25 to December 31.
Case 3 : Purchase price 18 with find next checkbox is ticked and date range between November 29 to December 31.
Case 4 : Purchase price 15 with find next checkbox is ticked and date range between December 29 to December 31.
You created a Purchase order on 5th December . What sales price does D365 calculate for the Purchase order?