It’s a kit, basically, a prefab shelter. They have a couple of different ones. In this case there is a three sided 12x12 pipe panel structure with three special pipe panels (either 4-rail or 5-rail) that have vertical sections to support roof purlins. Then I have roofing to screw into the top, two normal panels and a gate panel. They have another solution that is 12x16 with a 8’ roof.
http://scbarns.com/shelters/
This is the vendor in question but these kinds of prefab pipe buildings are available from lots of local places in California, welded on site, and usually the places that make them will do custom work too, though obviously with more lead time. There’s actually two such just in Sonoma County and I’ve bought from both. This particular place and structure, they just have the pieces waiting in the yard. Cost for what I brought home, including anchors, roofing, tax, and all hardware, was about $1200.
Of course today the smoke is so bad I can barely see my own trees, so that’s no good for getting it up…