WHERE to get the best price on air tanks?

Depends how are you planning to use that tank, if you planning to fill with your own compressor Chinese tanks is fine, if you planning to bring to Diving shop - it's no go

90% of Chinese tanks don't have a DOT sticker, at least in MA - Dive shop doesn't even touch that kind of tank.

eBay - for around $100-130 you can get 88 c/ft made in 2004-06, technically those have 15 lifespan, but in our Dive shop I was told it was extended to 30 and they would fill, as long as every 5 years, it can pass Hydro test. You can't beat that price. 

Not a lot of people know about lifespan extension and eBay is flooded with hundreds of tanks made in 2002-03, if you can spend a bit of time you can find 2004-06. I got just a couple weeks ago 2005 88c/ft tank for $125 with free shipping. Will have to do Hydro in 2020, even without extension, I'm fine till 2025
 
That's a good point. It just happened to me on eBay. I won an auction for Brand New Luxfer tank, nicely wrapped in plastic the last moment, before paying money, I realized not a single picture has a manufacture date. In every single picture, a tank was turned in a way, you can't see date. Sent question to a seller - sure enough tank was made in 2008 - canceled that 


 

I think the picture shows the tank was manufactured in 2015. It will have to be hydro tested in 2 years, right? Air hog is saying it is a new product. A person would also need to buy the valve, gauge and fill whip with fittings, looks like.


You'll get a brand-new one. Are you looking for just the cylinder or the whole shebang? I know where there's a new complete rig. Msg me for info if interested. Its a big tank, valve, gauge and hose for 500bux. Let me know.
 
I just bought a tank after spending a few weeks looking at eBay and several air gun forum classifieds. I bought an Interspiro 1/2012 DOM, 66 ft3 SCBA from airtanksplus.com. It's well used and came with a typical fire fighters Scott or CGA-347 valve, ready to use. I've bought a SCBA Hose Fill adapter elsewhere and soon as that arrives,I'm ready to go find some air....I looked for a bigger tank, but they got real pricey, real quick. If I stay in this, my next tank will probably be a new or near new tank. In the meantime, this tank will do fine. 

Be cautious on eBay, you have to know what you're buying cause most sellers don't care if you get stuck with a tank you can't get filled. If the DOM isn't clearly shown in the ad, go elsewhere. eBay tanks get expensive quickly when they have only a few couple of good years of life left. Mine was far cheaper for many many more years of serviceable life. If you have your own compressor (I don't...), eBay becomes a much better deal, buy as big of a tank as you can find that's just expired with a recent hydro and enjoy!