Buyer/trader shout out list here.
http://www.elektronauts.com/t/buyer-seller-feedback/1013
Use PayPal & don’t send funds as a gift seams to be the general approach.
Be wary of dealing with people that aren’t an active part of the community particularly if they only appear in market place threads!
If in doubt get a surname & address then check the Electoral register, in the UK anyway!
These things are always a gamble but remember the vast majority of transactions take place without a hiccup, you only hear about the one that go wrong!
Also consider collecting in person, might be a nice day out 