In my experience, anything that involves payment to/from Western Union is likely to be a variation of the well-kmown "Nigerian scam" that continues to operate in various market sectors (ie, certainly not just motor-bikes). The "over-payment" cheque trick is also very well known. You should be OK using eBay, though, especially if insisting on payment by PayPal. Bottom line is that anything that sounds a bit complicated is almost certainly a scam. Never trust anybody!
