I have item A price is $10 and item B price is $15. When A and B bought together the price is $20 ($5 discount).
Can this be done automatically without creating new item C that consists of A and B at $20? For example, if a customer bought 6 of A and 4 of B, the POS adds a discount of $20 (4 of (A+B) discount).
If this is not possible, can the POS merge items instead; Convert 4x(A+B) items to 4xC items with the promotional price?