@Lynn Dollar it's not surprising that a welder would want you to haul your Brazos into their shop. Obviously, if they have a full mobile truck or trailer, that's a bit of a different story. If he (or she, I shouldn't make assumptions,) is going to be cutting, plating & welding, the weld lines need to be squeaky clean, and they'll have all of the tools at their disposal in their shop. Oh, and power.... while you can get good welds with 120v welders, they'll either be relatively thin or multiple passes (smokers should be under this limit, though.) Just makes it a whole lot easier.
Having said all of that...... my g/f put the firm squash on acquiring a used propane tank and going down that fabrication road several years ago. Personally, I'm now quite happy with my fully insulated gravity fed cabinet, it just plain works for me.