I think the logical thing to do... besides writing him off completly with the fear that hes going to screw you... is to sit down with him and ask him some questions. Take the business approach... ask him what he can do for you and what you woudl get out of it... and what would he get out of it... you also might ask for some references... maybe some other bands that he's worked with or some venues that he's promoted to. obviously he's going to give you references in which he knows will give you a good opinion... so in that light you can do some of your own research and seek out bands that may have worked with him... it could be a good thing for you as a band... it may not.