What happens if someone sends me payment from a stolen CC via PayPal? Will I loose the money or is it the credit card company's issue? Or is it PayPal's issue?
PayPal puts a hold on the amount after getting complaints from the original owner's credit card company. After investigation (10days usually), it can either be added or reversed.
Or worst your account will be limited. But if you have good rep in pp they will just hold on the account and refund it to the owner of the pp account that is stolen.