Canvas tents breathe, car shelters are plastic bags.Humidity is trapped in there and they turn into a sauna, not to mention, fumes from any fuel burning appliance. Might regret your choice.
Grizz
Very wise advice Grizz, Those Shelter Logic type portable garages that Canadian Tire sells may look like a good idea but their not. The main reason being they don't breathe. They will condensate inside to the point of constant dripping even with a woodstove set up. Several times I have been invited into one of these set ups to socialize with the boys and I observed and heard the stories of the constant battle with condensation and things getting wet from the dripping.
The teepee idea sounds like a good set up, but they weren't around commercially when we were in our hay day. I guess the natives knew a thing or two. Inventing the canoe and teepee