There used to be a few problems for buyers, but mostly they have been sorted out by Paypal now so you should have little trouble in that respect.
But there are scams for buyers.
The famous one was Xmas before last. Mummy and Daddy bought little Jonny the latest PSP/XBox he's been screaming for. It arrives in a nice shiny box complete with cellophane wrapper intact. Mummy wraps it up and sticks it under the tree. Imagine little Jonnies face when he opens it and finds a ................................
brick......oh the joy.
Too late now, the seller has long gone along with his scammed millions.
That one hit the Watchdog TV programme.....
Just don't link your PP acc to your bank acc....

As a seller you have to make the link or you can't withdraw your income. I believe now you can't accept any PP payments for your sales either which would be a problem.
If anybody wants a real live demonstration or has any doubts just show me one of your live auctions. I will bid, pay, have the payment refunded and keep the goods. It's really quite simple to do.