Not knowing what LWS the owner of the business uses It's hard to say. There may be some small supply houses that still do things like they did in the old days. Airgas has bought up just about any store front that has anything to do with welding or gas supplies and I know the corporate office pretty much calls the shots on any of their branches no matter where they are.
Airgas bought up my old welding supply house, Arcet and I had about a dozen smaller tanks of varying sizes that I had bought from them and when Airgas bought them out they would not refill them any longer. A couple of those tanks I had cost almost $500 and all they were good for was maybe a mail box post, the scrap yard wouldn't even take them unless you cut them in pieces.
I didn't want this to turn into a heated debate all I wanted to do was to bring this up so that the OP could at least check it out before they went out the door and find out later that they were rental tanks that they will be responsible for, that's all.