There are some lessons to be learnt here OP:
1) Look at the trust rating of the user (both trusted and untrusted feedback, but take the latter with a big grain of salt unless there is substantial proof).
2) Do not trust anyone.
3) Use escrow when you're dealing with members who do not have a verifiable history of trades (which often coincides with a higher trust rating).
In the case of the user in question, he or she has possibly scammed at least 1 more user in the past:
I've left them a negative rating.
1) Look at the trust rating of the user (both trusted and untrusted feedback, but take the latter with a big grain of salt unless there is substantial proof).
2) Do not trust anyone.
3) Use escrow when you're dealing with members who do not have a verifiable history of trades (which often coincides with a higher trust rating).
In the case of the user in question, he or she has possibly scammed at least 1 more user in the past:
I've left them a negative rating.
He has paid through skrill, although it was risk, i accepted, and just to confirm it was legitimate transaction, and i was away.
I have already transferred him bitcoins. I dont know why negative feedback has been left.