First of all, why are you giving proposals via email text and/or verbal communication? That's asking for trouble and now you see why.

Second, is your final payment free and clear, or at least the deposit which if you're smart covers at a minimum your costs associate with the job? If it is call her out, let her know you're calling it even for the wire fraud she committed, the job is complete as is and part ways. She can find another sucker to do future service calls.

You're thinking you will get the 40-50 dollars or whatever it is out of her to cover the office girls OT? You're crazy. And trying to collect on that will cost you far more. Move on and learn from this.