If a buyer is not happy with the good received, say for example they are not in the condition described*, then I would expect the seller to refund the original price**, when they have received the goods back. Obviously a buyer will have heeded STW forum advice, and used paypal (not gift) to purchase the item, so there will be no problem getting a refund (paypal side with buyers). The seller would not be expected to pay for the return of the item though.
Just my take on it, others may disagree
* – I’d say there an expectation that the item is not as describe, rather than the buyer has decided to get cold feet.
** – though as the seller has been placed out of pocket by sending the item, the postage may be negotiable, as the seller will have sent the item in good faith, but then if the item is not as describe… bit of a difficult one really.