This did not happen to me but happened to a friend and Hieuxx tried to do the same thing to me.
Said he wanted 7 digit and 8 digit and would not go first.
He said he'll take the 8 digit, pay me, then I would give him 7 digit.
I gave him 8 digit and it obviously logged me out.
He denied it and said it didn't work.
Click Here for More proof.
My thread. Steam Accounts! 7+8digs! 6digs Coming soon! Also Ventrilo.exe legit AIMBOT.
Another report of this guy here: http://sythe.org/showthread.php?t=648122
Here is the screenshot with the steam disconnect and him denying it in MSN.