Difficult to carry off if you've made the purchase and when it arrives the serial number number is wrong. I mean, you have evidence of the thing you clicked on don't you? And there are countries where 'never give a sucker an even break' rules over any possible and residual code of ethics the Japanese have. I recently bought from Japan on eBay a Voigtlander SP 35mm Skopar for my Nikon SP, described as mint condition, delivery 21 days. It was mint when it arrived, perfect in fact, and it arrived in three days from Japan to the UK. The only time I've had a problem was a Nikon F2 and with a DE-1 head, but when I put a DP-1 head on it didn't work, solution, clean the battery contacts. There is a lot of hand wringing and worry about bogie men out there to get you, especially dealing with foreigners, and it's largely paranoia.