Some things that you could do to protect yourself better when you sell, at least this is how i do:
1) Request the buyer paypal email:
2) Check if his account is verified (may be US or non-US verified)
LINK
3) Send a payment request from your account including information about what are you selling and any other transaction details you have.
* In the verification link you have to replace 'email' for the email you want to check.
