When you charge by the hour, you can't give a price until after the job is finished. And we don't want you to have to wait till the end of the job to find out how much it cost.
We believe there are too many variables that make "charging by the hour" more of a win for the company, not the homeowner. If an HVAC technician has to go get a part, is slower than another technician, the job takes longer than expected, etc. -- are all things that a homeowner has no control over but ends up paying the price for. There's no accountability on the HVAC company to have their trucks stocked better, train their plumbers better or run their business more efficiently.
There are many other reasons but they all revolve around us trying to do right by everyone involved; the homeowner, the HVAC technician, and the company.