I bought mine from a dealer as a demo model, and that was close to the price I paid (I paid a bit more because I'm in Canada.) You want to make sure that the warranty's intact, and I'd make really sure it had been serviced between its use and your possession of it - mine has feeding issues that I have yet to have corrected, because the original dealer refuses to admit that there's something wrong, and I haven't had the cash to have it serviced elsewhere. Other than that one thing, it came as new and it's a perfectly functioning machine in every way. (I think it's a timing issue that I'm having trouble with. I hope it's just that
From what you're describing, it was the same situation - my machine was used in a classroom at the big Toronto Sewing expo (CreativFestival). It was a very good deal, just make sure you can't get a better one from a dealer in the area, as these machines are being discontinued in favour of the 500 series. (550 is the new quilter's edition.)