this is about money! It isn't dating!!! He's doing it for the money and not because he is a nice guy/bad guy etc.

I would call him up and Monday morning and say, "Thank you for your time, but having seen too many mistakes, and hearing of suprise at the end is not my cup of tea. I can not go forward with your office."

Straight simple and to the point. If he starts laying on the personal guilt stuff then its really unprofessional. RUN!!

just my 2 cents.