A5 Heating and Cooling Inc Incompetant service. Rip Off prices. Will not provide receipts for parts purchased Lisle, Illinois

A5 Heating and Cooling is a big Rip Off. Never gives you a quote in advance. They took 7 hours to figure out what was wrong with my heater and charged me around $500 for it. The cost of replacing the whole heater would only have been $900!. They charged me an arm and a leg for simple parts which would have cost no more than $10 in any hardware store. When asked for a receipt, the guy gave me a printed piece of paper (Apparently, it was their warranty bill)  which didn't have their contact information or anything. Still no receipts for the parts purchased!!! I was too naive and tripped on their tricks, but I would warn anybody to stay away from them!!! BIG TIME RIP OFF!!!!