I see these scams on a daily basis.  Generally its people selling a car, caravan or motorbike in a hurry as they've moved to England (send photos from google or the trading post of other peoples ads)...

Ask the seller, to take a photograph, with a peice of paper on top of it with your name and date - or anything, just to prove its legit...

You'll get some crap that the parts are not near them at the moment, or its in storage...blah blah...They might even supply you with a mobile, which will work and you can talk to them but still a scam...

Any other time if buying from a person direct, avoid Western Union / Money Grams....There are teams of mules working in the UK, laundering the funds then off to Nigeria.

Its a shame they're moving into the pinball scene....