Definitely on the line between craft and shop. They're (mostly, if not only) selling a product they designed, but they're manufactured elsewhere and installed elsewhere. Apparently they don't keep a lot of stock anymore and want you to reserve a product in advance, so I'm leaning more towards craft. As far as the value, there really isn't a better word than shelter. Some manufacturers use "portable garage" or "fabric carport", but they all seem to just call these things "shelters".