ARS Rescue Rooter overcharged and did not fix AC problem Columbia, South Carolina

I was charged originally $89.00 but after giving him the coupon I had I was charged $35.00. 

The house continued to get stay warm and on August 2, 2010 I called again and Jeremy came back out. He continued to check the unit again, could not figure out what was going on, called his office a number of times to see if someone in the office could shed some light on the problem and after an hour and a half I was told that my control box was not working correctly and it needed to be replaced. I was given a quote for $1600.00 to replace the control box and 2 thermostats. I was charged $300.00 and was told that was a bargain as the company normally gets more than that for electrical work. I paid the bill but was not happy. 

In the mean time, since I have some knowledge of AC systems, I saw that the control box was rewired so heat would come on when the AC would kick in. After wiring the box back to where it was I now have AC but the unit will not shut off unless I shut off the circuit breaker but at least my house stays cool.

I have looked online for the control box which I would need, if that is the problem, and have found that American HVAC has a Carrier control box and thermostats, part # ZONE CC2KIT01-B for $543.00 plus shipping. 

Where does ARS Rescue Rooter get the guts to charge a consumer $1600 for a repair like this, if the control box is the problem?

I would like to have my money for the second service charge, $300.00, refunded as the so called serviceman did nothing but waist my time.