problems with undelivered packages.

good morning, I have a serious problem with three sales on my account, I sell graphic kit for motocross. The issue is that for some countries the national mail does not work, as the Netherlands or Saudi Arabia and even Germany. buyers must go to the post office to claim your package and pay a nationalization tax, usually is little money, but if not paid the product is retained and is not dispatched to the customer and after 15 days is returned, now I have a case where a customer had his bike stolen, something that is out of my control, not claim the graphic because he says he is no longer interested but that product was customized and sent by us. Most likely it will be returned and then I will have to give a refund losing all the money for the customization and shipping. I wonder how ebay proceeds with this, because I notice that many take advantage of ebay's policies.