spoiler alert - you may think twice about using paypal if you follow this link:
http://www.paypalsucks.com/
I found the site years ago when I had the one of two HUGE problems with PP that I've had in the years I've been using it - they cost me $1500. I purchased a 1st issue of Playboy from a seller from I forget where. It was supposed to be shipped overnight. While the "seller" had been quite communicative up to the point I paid her, she was supposed to email tracking information which she never did. Being suspicious already, I called Paypal and asked what happens if I dispute the transaction - I was told the money is "locked" in the sellers account until the dispute is resolved. I said okay, thank you, I'll give it till the morning before I dispute it. When I had no communication by the morning (less than 12 hours after I had sent payment), I decided to play it safe and file a dispute. I did. I don't recall the timeline, but I got an email from paypal saying there was no money in the sellers account to lock - I communicated the conversation I had the night before with a paypal rep. The silence was deafening. Paypal did NOTHING to resolve this for me or get my money back - they aided a thief and communicated incorrect information to me.
Further based on my experiences and those of others I have spoken to, PP seems to have a stupid amount of control, very few rules that they are bound by and virtually no reasonable recourse if they harm you.