Hello! I have a website where users can buy digital goods and checkout with paypal. Basically, I was wondering how can I protect myself from people buying something with paypal and then claim it was an unauthorized purchase. I previously had an experience where I sold someone a digital good and then they opened a dispute. The exchange was done manually and not through an old fashion paypal checkout page. My site is using the paypal checkout page and I'm using Paypal's IPN to confirm the purchase. What should I do or put to help increase my chances of user's trying to open a dispute and winning when I'm selling digital goods. Thanks!