I am considering buying a 1.5 year old used Focus Temp Insta pool pump for my 24 foot above-ground pool. The seller indicates he paid $1200 for it new. (I found an ad for one at $1196-although it was out of stock). I am concerned because the price for this pump is significantly less than any other heat pumps I have found. Do you know anything about this particular model and any reason why it is priced so low? Any input will be greatly appreciated.