Thank you everyone for your ideas and input. I was thinking about Mitsubishi. That one heater from Home Depot sounds like a decent idea, but I will need to find a way to route nat gas to the garage. It is well equipped with outlets, as it has about 14 of them! I might insulate the ceiling. The garage is constructed of cinder block. It generally stays about 10-12 degrees or so warmer than the outside. Also, my door is off the floor a little bit on one end, forming a narrow wedge shape. Can my door be shuffled around after loosening some bolts, to make it sit flat all the way across the opening? I replaced the rubber gasket on the bottom of the 2-car door 2 years ago.