I'm looking for a temporary heater solution to make my garage a little bit warmer when I'm working in it. By temporary, I mean something portable, not a fixed unit. My garage is 30x40x9, fully insulated, with painted drywalled walls and ceiling. I don't think I want anything that burns fuel as it may darken the walls and ceiling. Maybe some sort of infrared heater? I'm not looking for 75* temps, but 60ish would be ok.