I too had a similar problem with PayPal. I sold nearly $1800 of kit to a single buyer. Said buyer held on to the kit of nearly two months without any communication with me and then hit me with a dispute claiming one of the items had serious faults. PayPal immediately locked my account. Luckily the descriptions I gave were so explicit I won the dispute. It took nearly three months to sort this out before my account was restored and nearly a year before my Ebay feedback got to 100%. In my discussions openly admitted that they favour the buyer in these cases leaving the burden of proof on the seller.