The most crucial credential for the customers is their Payment details. So first make it crystal clear that our payment system is fully secured and there is no possibility of any discrepancy. The payments system-doesn't reveal the payment details to our employees even. As the secure payment gateway server doesn't reveal the payment details. So there is no probability of any conflict. Furthermore our payment system explicitly declares the total amount to be charged from every customer hence there are no hidden costs on any transaction.
Every customer has legal right on the product for which he/she has paid. Hence the product can be used at any instant depending upon the permission of its owner. No one has the right to use the product without permission of its owner even writerkingdom itself.