I don't thinik it's a great deal but
IMO it is an average deal...something that if you pass up you'll see a similar one a week down the road. If the tank is that new and if it comes with everything pictured like the protein skimmer, then it's obviously a better deal. The question is, what are your plans for the tank? Do you want saltwater or freshwater? Also, what fish do you intend to keep? If freshwater, are you looking at going with live plants because that lighting isn't going to be sufficient nor would it be sufficient for corals (
SW). Also, you are going to have to purchase a heater and a filter most likely so keep that in mind. If it were me, and all of the stuff were included that is shown, I wouldn't pay more than $325 for it, but I doubt he will take any less than $400. My guess is that his bottom line is $425.
EDIT: Did a quick search near me and found this:
http://kalamazoo.craigslist.org/for/894061193.html I was only $5 off what I would have paid! Not too bad eh?