I can ask you something, it is allowed that a user sells bitcointalk account yes or no, and because they reason, because I would like to work on that topic reporting
To summarize my last reply;
Just don't do it. It's not worth it as you are potentially aiding scammers and signature campaign abuse and as you can see people are already sick and tired of the signature campaign abuse which is going on.
Heed SaShiRaJaVu advise too. Without using a escrow your likely to get scammed yourself, and no escrow these days are going to help the sale of accounts.