I just paid $92 last week including freight for a new 10 lb aluminum tank from a vendor on ebay and it looks of excellent quality. It arrived in 5 days. The vendor answered a couple of questions for me and suggested to secure the tank in some manner as more than one person has knocked the tank over and smashed some part of the regulator, like the needle valve. My tank is secured.
My gas supplier wants $200 for an empty 20lb cylinder, so buying online is a far better choice for me, even considering the new cylinder will be swapped away at first fill. It's worth checking, but most of the time you'll have to contain your laughter when they tell you the price... ....or in my case, the guy at the gas supply was laughing with me and told me to just get one online.
found an old beat up aluminum tank at a scrap yard belonging to family. cost to me: o dollars. took it to welding supply 1/2 mile from my house, paid 14 dollars for pressure test fee and 19.00 to fill and they gave me a shiny new cyllinder full of co2. yay for me!!!!!!!!!! I'm up and runnin.