lol.... he's obviously still struggling with 'car loss syndrome' and can't think about anything other than garage=car.
Actually.... speaking as one from Florida... just put in some roll out Owens-Corning insulation in the walls, sheet rock over, tape and mud. Paint. Then put a few halogen lights (torchere ones work really well). When you need heat, turn em on. The place will stay warm enough. Trust me!!!! :D Works for me!
Note: if you're going to enclose your garage... you really should talk to your town office. You'll need a permit and inspections. But... it will be so much less hassle in the long run. Consider putting in a window where part of that garage door was.
OR... .if you're going to only do this as a temporary thing (leaving it so that you can use it again as a garage later....) then leave the garage door un covered. Instead, insulate the back of it with the foam insul board stuff, cut to fit between the back struts of the door. You can then get a king sized flannel sheet and pin it to the back of the door/foam and have a HUGE design wall - instantly!