I'd pay $800-1000 if it's not all scratched up, no leaks, no water damage to the stand, and dependant on what hardware comes with it (heaters, pumps, filtration vary greatly in price/quality/durability).
That being said, after I really inspect 99% of the stands out there that are a couple years old, most are rotted junk. I'd just buy a tank and build my own stand if I were you. Second hand stands suck.