Discount/Coupon for user defined amount

I am currently gets the numbers with user defined amounts that routes through Paypal. I would like to offer discounts/coupons for people that qualify. The way I currently understand it, I would need to select to "sell products" to have the option for discount/codes. Is there an option for user defined amount to use discounts or do I need to restructure my whole form?

Unfortunately, the built-in coupons option is not supported for user defined amount product type.

Since you use calculations to calculate a total amount, you might consider adding a standard field and combine it with conditions to create the coupons manually.

Note that conditional 'coupon codes' are not hidden in form source code, so advanced users might be able to find them.