Price gouging seems like standard practice for HVAC companies.
I'd like to replace my 25+ yr old system (gas furnace/AC) with a new gas furnace & heat pump so I can have the option of heating with gas or electricity... but when I ran this by an HVAC technician who was here for a service call, I got the same kind of exorbitant figures thrown at me with the heat pump in the equation.
Same technician wanted $750 to replace a control board when my furnace had gone out during a blizzard - I sourced my own & did it myself for <$150.