I had an overeas bidder win an item, and the adress was in the U.K.  When I sent the invoice, I had calculated the postage, etc, to the U.K.  When it came time to pay up , (using paypal), the buyer had changed their mailing address to China. Trouble is, this item is a prohibited import into China (I checked on AP's restricted imports website). So I sent an email to them explaining that this item was a prohibited , cancelled the sale, and then refunded. All fixed- or so I thought.
I re-listed the item and guess who won it again?- My original bidder- So this time, the address was in the U.S. So, again I invoiced with postage to the U.S., thinkng they may get their "Friend" in the U.S. to send it to them. This time I kept a screen shot of the original order with it's U.S. address. When they paid up, the mailing address magically reverted back to china again! I once again cancelled the sale, refunded their payment, and put them on my "special bidders" list.   If I had sent this item to China, it would have been picked out, confiscated, and I would be out- the item ,plus the cost, plus the postage! If sending stuff overseas, it pays to check out AP's website, they have a list of countries and their particular import restrictions- some of them are pretty odd!