I think the answer lies in a third party broker that's does more than just transfer money. Paypal should either purely transfer money and stay out of disputes or be a third party escrow type place that the sellers ship to and then, after confirming that the item is what was listed and adds an inspection security sticker, ships the item on to the buyer. This way the only claims possible would be for lost in the mail, in which case the shipper would be covered via postal insurance. It should really be that easy. I think there is a need for this in the market and the right venture capitalist could get rich quick...