I just looked up the energy star list of high efficiency heat pumps, chose the largest model, and googled a few of the prices to get about 7 to 10k. Which is still absurdly high for what they are, but I was looking at the highest efficiency ones so I guess they have fancier compressors or something else that lets them raise the price. I also got an average cost to replace an AC unit of 500 to 2500 dollars.

At the end of the day a air source heat pump is just an air conditioner with a 10 dollar reverseing valve, though they typically use very efficient air conditioners and add an emergency space heater aswell. Well if your being predantic an air conditioner is a heat pump, but generally in climate threads heat pump is shorthand for one that works in reverse for heating as well as cooling.

I really can’t imagine the level of grift you would need to have to get from that to 22k, unless you were using ground source or retrofitting central heating into a building that previously lacked it, though in that case you would probably use several minisplits to replace individual radiators or baseboard heaters.

I looked up prices in Massachusetts, they are higher than the national average. Looks like 2 main factors:

1 A higher than usual percentage of mini splits vs central air. These will be more efficient and have a lot of comfort benefits, but are considerably pricier then retrofitting a central air system. So if you are retro fitting CA, you could come in under average.

2 MAs impressive $10k+ incentive system for whole home heat pump systems has resulted in HVAC companies raising prices, because of course it has. This is why we can't have nice things.