-Keep users from changing an amount of a price if it already has users who have used it. Just let them disable if it and make a new one if necessary.
-Keep users from changing payments in ways they shouldn't, such as refunds larger than amount paid, etc.
-Ensure that credit card amount paid can't be changed.
-Anything else??
-Keep users from changing an amount of a price if it already has users who have used it. Just let them disable if it and make a new one if necessary. -Keep users from changing payments in ways they shouldn't, such as refunds larger than amount paid, etc. -Ensure that credit card amount paid can't be changed. -Anything else??