Hah, although, admittedly, when my AC died here I was looking at quotes for $17K for replacement (although I did also do the furnace at the same time, since both were early 1980s and basic models even then). "Why? I could buy the AC for $4K".

"Surely it wouldn't be too hard to undo/redo piping etc." But yeah, different refrigerant, different code requirements for vents and exhausts and drains. 4 people working for 16 hours, I saw where the money went.