Is there a longer explanation somewhere for exactly how this works? First I set the price to 0.00 and checked the editable price box, and got customer feedback saying they couldn't change the price. I searched the forums, read a post that said I needed to set a minimum price of at least 0.01, and then it would work. I got customer feedback saying they couldn't change the price, and a bunch of them wound up paying $0.01 when they wanted to get it for free. I set up a new PayPal account to test it out (because you can't send money to yourself on PayPal) and wound up getting my IP address blocked ("free checkout for your IP address blocked due to abuse").
Ideally I'd like a page I can send my customers to, or at least know a step-by-step explanation that I can give them. Right now it looks to me like I set the price to 0.00, check the "editable price" box, and then the customer can add the item to their cart. Before clicking on the PayPal button, they need to set the price to what they want to pay, and then click "update." They can then click on the PayPal button and check out. Yes?