Because you are using “individually priced files” to sell content, you will lock all people who have previously paid at that amount out of their access if you change the price of those files. You will have to keep the files at that price point if you wish those to keep access. If we get requests from people that have lost access then we will refund their payments. Unfortunately there is no way around this when using “individually priced files”
For pages where you want to set a purchase price for the project then we recommend setting the minimum price on the project. That was if you change the price it will not affect ownership.