You're never going to get a 100% guarantee. You can take steps to help, though. If it's above a couple hundred dollars then require a signature, which gets rid

You're never going to get a 100% guarantee. You can take steps to help, though. If it's above a couple hundred dollars then require a signature, which gets rid of most issues. If you have a history of selling, and have a signature, there's a chance they'll side with you. eBay is slightly better for one-off sales: you can refuse returns (if specified in the listing), and cancel sales by buyers without verified paypal accounts or no feedback. Plus they have a sellers guarantee, although I don't know how often they'll actually stick up for the seller.