Fast Appliance Service Cash payment required for house call. Exorbitant estimate given. Stony Brook New York

My 10 year old through wall AC unit stopped working.  I called Fast appliance service after I found their ad in a local paper.  They told me they could come that day but would require a $150 cash payment for the service call, to which I agreed.  It was a hot day in August.  When the serviceman came to my house I showed him the AC unit.  Within 5 minutes he told me it was the main motor.  He went to his truck and called his office.  A few minutes later he comes back inside and shows me a written estimate,  The estimate shows a price of $1247.83.  The unit only cost $589 when I bought it.  I told him that estimate was crazy and I wouldn't pay double the cost of the unit to get it repaired.  I told him I feklt scammed because the never intended to fix my AC, they only wanted my $150 cash.  After he left I called the office phone # and asked to speak to the manager.  I was told he was not available.  When I told the receptionist I wanted to complain about being ripped off she put the manager on the phone.  The manager tried to convince me of the amount of labor required to change the motor, blah blah blah.  I told him his company was a scam and I wanted my cash back.  He hung up on me.  I found out the motor was only 220 on line for the part, that would make the labor $1000.  I ended up buying a brand new unit at P* R****** (((REDACTED))) for $611 and I installed it myself.