Yeah, I think people realize that good deals can be had buying used equipment. Of course, it goes without saying that buying someone else's corals is good because they have been in somebody's tank and obviously have not died. But on the flip side, that doesn't mean it won't die in your tank! [D]
Here's an instance where the seller got the better end of the deal....
I first started, I didn't know much about marine systems. I bought a person's tank off ebay that was local. It didn't meet the reserve which was $1000 and the highest bid offered was $660. I should have taken this as a sign, but I didn't. I contacted the seller and saw the tank. It looked "pretty" to me because all I saw were pretty fish. He told me all the green hair algae (and there was LOTS) was a sign of a healthy tank. I didn't know much about equipment or anything marine related.
I offered the guy his asking price of $1000. He advertised it as a 150 gallon reef tank that was running for 3 years. Basically, the guy had a couple nice fish and about 4 corals, torches and leathers. He called it a reef tank. What did I know back then? [-gnasher]
I told the guy I was cycling my 75 gallon tank and that I would take parts from his tank to transfer into mine. I told him that I'd get the livestock when my tank was done cycling. He said no problem, that I'd have until the end of September. At that time, it was the beginning of September.
Well anyway, it was extremely laborious work travelling to this guy's trailer home which was a good 40 minute ride one way. We did this countless times back and forth to his house. By the end of the second week, he told us he wanted everything out of his house. So much for my tank being able to cycle properly.
When I tested his water, it had 70ppm Nitrate! [-bigeyes] [-censored] I didn't have anything else to test the other saltwater parameters. I knew I didn't want to use his water or else I could have my very own algae garden.
He said to scrub the rocks to get rid of the algae. Not only did I scrub them, I blasted the heck out of them with the garden hose. I'd show that algae a lesson or two and every other good bug in the rocks too! [-banghead]
Well, to make a long story short/shorter...the equipment I got ended up being so pathetic. The guy was using a Berlin Skimmer with a wooden airstone + pump. His pump was broken and he never bothered to get a new one. I wasn't told that until after I handed over my money. The really great metal halides he bragged about were the kind of bulbs you'd use to light up the aisle way at WalMart. I could go on and on.
I ended up having to buy all the equipment new, lights, filter, skimmer, powerheads. There is absolutely NOTHING in my 75 gallon tank now except for a few rocks and a mandarin fish that came from the 150. I've got more coraline growth on the rocks now in less than 5 months time than he did in 3 years time. Oh yeah, when I took measurements of the tank, it was a 135 too. I ended up selling all the equipment at dirt cheap prices. The equipment was "usable", just not what I wanted.
I should have just taken my $1000 and bought what I needed for my 75 gallon tank. I would have come out so far ahead. I didn't do my homework and I didn't know better. Instead, I gave money to a conman who sold me something that was certainly less than advertised. [-censored]
So you see, selling and buying can work both ways.