I'll pay 1.00 per gallon with accessories on CL since bare tanks you can get for that on sale. Older doesn't bother me as long as in good shape and holds water, but I prefer black trim to wood. I recently picked up a great deal on a complete 125gal aquarium with lid, lights, metal stand, two canister filters, and some other accessories for 100.00. It was brown trim, but I've made the best of it! I find better deals in small towns. When it's in a big city, people like to ask more. The post I thought was actually pretty well thought out though, and the market does depend on location.
There's an ad on my local CL that's been posted over and over for MONTHS for a 30 gallon tank for 115.00, and each time they post they specifically say "If you like to dicker, I'll gladly accept more." Hmmm wonder why it hasn't sold yet? I'm not one of those flag happy people, but if I was, I'd flag it for just annoying me.