Contractor invoices WAY over estimate....what can I do?

[Charles Thompson]

I'm here asking for some advice about a problem I'm having with a "contractor" I hired to rehab a flip.  I'll post a follow-up with more detail, but the gist of it is I signed a contract with who I thought was a licensed GC (turns out he is NOT) to manage a reno project.  He turned in invoices to me for WAY over what he had quoted without any forewarning of the cost overruns.  These are the invoices given to him by the subs that HE hired to do the work, but as it turns out he never even had them quote the jobs before hiring them.  When I balked at the invoice he handed to me, he says "I just want for my guys to get paid".  I should add that the contract stated the job would be done in 45 days but it took 128 days.

I want everyone to be paid fairly and I certainly don't want a lien placed on my house by some sub I've never met and didn't hire.  But I can't afford to pay the invoice he is giving to me.  

I'm wondering how to best handle this situation.  What, if any, legal options do I have?  My goal isn't for him to pay for my rehab, but a gc/project manager shouldn't have free reign to spend the client's money over and above the contract price without forewarning and an explanation.  Anybody have a similar experience, and if so how did you handle it?