I'm banging my head with rounding when paying with cash. I have a product with price of 1,82€ and I've created a product called rounding. Now when I add the rounding and select it's price to be -0,02€ it adds the 0,02 to the total and if I add the rounding as -1 each and set the price to be 0,02 it also adds it to the total. What I'm doing wrong here?
I know that there are two apps that takes care of this but at least the free one doesn't suit my needs because when people are paying with credit (or debit) card the prices shouldn't be rounded. The other app I just cant afford.
mark your product in model is_round similar to is_delivery. exclude it from totals till the last. then deduct it from whole total. this would make things easier during accounting too. to trigger calculation, use select field with on_change in sale_order and update field on return.