Your either going to have to find someone else to co-sign or wait until your 18 years old and dont need one. The lease holder is depending on the co-signer to make sure that payments are being paid either by you or them, if they have bad credit it shows that they arent that reliable and you can hardly blame the lease holder for not allowing it. How much longer until you turn 18, is there any way you could just wait, it would be alot simpler that way.
i honestly dont know but id say that you would be better off finding someone without bad credit
You either have to find a new co-signer or search for a place that doesn't demand one.