Paypal and buyer/seller protection outside ebay
Not sure where to post this. It's about Paypal and seller/buyer protection. I'm unable to get this cleared out for myself. What happens if somebody transfers money to my paypal account for an item sold by me on a site that doesn't have agreements with paypal (say APUG), and then claims back his money on the basis of "item not received"? Suppose that for whatever reason I can't show paypal his signature for receiving the item, will I lose that money? Or will paypal tell the buyer that he should have bought through a paypal-affiliated site? And if paypal lets down the buyer, will his credit card company (if that's what his paypal account is coupled to) be able to reclaim the money no questions asked?
I've been wondering about this ever since I sold a 700 Euro lens to a US buyer on the RFF. The lens took long to arrive and the buyer (understandably) 'threatened' to open a paypal dispute to reclaim his money. In the end the lens arrived and all was well, but what if the dispute had come about? Would paypal have denied him a refund because RFF-ads don't include a dedicated, paypal-approved, shiny yellow/gold 'buy-it-now' button? Would his credit card company have come to his help if not paypal?
Basically my question is: how safe am I, as a bona fide seller, from fraudulent buyers, if I sell outside ebay? Paypal policy just isn't clear to me on this.
Thanks for any insight & sorry if this is not the right place for posting.