Con man Contractor, what is my next move

[Amy C.]

Got a fantastic quote from a contractor from the neighborhood that approached me when I purchased my first rental.  Stupidly gave him 50% up front for "materials", then he went dark for a month and later found out he went on vacation.  

He came back, and after some neighborhood association pressure,  completed 20% of the work.  

Today he approached me with a misogynistic sob story blaming his wife and asked for the rest of the money to buy "materials" to finish the job.  If I buy the materials, he has no incentive to finish the work (no payout) and I half wonder if he will use them for another job.  If I start over with someone else, it will cost me 2x as much.  Also now finding out he is a frequent flyer in small claims court.

How do I get out of this and never get in this situation again? This is a terrible feeling.