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They are moving and not selling it with the house.
Also ask if it comes with the breaker box. Not a major deal but it'll save you from having to buy one.
I just bought that same spa a couple weeks ago. the one I got was only a year old and didnt have the stereo. I paid 3500 delivered and set up. I bought it from a dealer of another brand, he had this as his personal spa at his house. im in NW Montana, so the market on used high line spas is probably low. I wasnt scared off by not having the warrantee. a lot would have to go wrong to cost the difference from what I paid and a new one. we have used it several times a day for several weeks now and no problems. the circulation pump that runs most/all the time is the same consumption as a 75 watt light bulb per the manual. electricity should be pretty low. r