Well depends...
What is the stand made out of,
those press board stands aren't worth much IMO
wrought iron is a better bet, except no storage, but sturdy and now water logging
a hard wood stand, like oak with storage is good also
Has the lighting been upgraded, or is it standard
can the hood hold flourescent bulbs that can be changed to something else or is it incadescent bulbs...the are fairly useless, but alot of the cheap set ups have them
IMO, I would say that if it's in superb condition that 1/2 of what you paid is about as high as what I would pay for a freshwater set up used.