A few moments ago, I was selling my key. some jackass offers his strange sniper and a wanga prick. he told me the wanga was worth a lot, so I accepted. I told him to return, he bassicly said "f✿✿✿ you" and removed me. this is the guy: http://steamcommunity.com/profiles/76561198027931834 He is a scammer, end of story.
Just a newbie too, but you'd have to fill out a proper report. You show only his profile, and have no chat logs. Just my two cents.