Tanks are the cheap part. Equipment and livestock are expensive.
And there are two problems that make it worse:
1. Many (most?) people start off with cheaper equipment, thinking that they can get by, and then end up re-buying a lot of the same stuff. I know I did with a lot of stuff.
2. As newer better equipment comes out, many of us either either tech obsessed (It's okay, I like new stuff too, to an extent) or realize that there is a better, cheaper, faster, more fish/coral friendly way to do things and buy that new stuff. I'm sure I'm not the only one with like 5 extra mid-range pumps, powerheads, skimmer bodies, etc sitting around collecting dust.
My tank has been very stable for about 2 years now, doing well, etc, but I just upgraded to a new (used) lighting system, new return pump, new dosing setup, new controller, new frag tank, and am buying a Vortech this week. Man, that makes my wallet hurt just typing it, but I know I'm going to order that and bulbs this week. haha The good thing for people starting out, if they are patient and do research, hopefully the can learn from my (our) mistakes and buy good equipment, such as from this thread.
Kerry, sorry to help further derail your thread, good luck with the sale.
Matt