All I can say is if you are using PayPal to pay, you don't have to worry about being scammed. Seller is taking a huge risk by doing this and he knows it. I didn't buy, but what kind of buyer info do you need before a purchase? Or is there some specific way you need to pay with PayPal?
It works exactly as anything that you decide to buy with paypal. Once the order completed, it brings you to paypal, you have the choice to login to your paypal account if you have one, or else pay with a credit card. You have to enter your adress and info (I assume it must match the credit card adress).