It gets expensive when you have someone else do the work. I honestly don't believe I could own a class A if I didn't do the majority of the work myself.
This spring I moved the head banger TV to a lift cabinet and reconfigured the old cabinet to be the same size as the rest. I did a bunch more little stuff,lubing the battery drawer slides, washing waxing, treated the roof, replaced the dash heater valve, fixed chips in the windshield ,etc etc and spent around $4000.
I'm having the inverter replaced and a Progressive surge protector (which I already bought) installed by the local RV repair outfit for about the same amount.