OK to get back on subject, sort of. Here are some pics of my Pontiac garage. When I needed more garage space I added two stalls on the back of my existing two stall atached garage
There is a 16' insulated overhead door that seperates the two. It is heated with a ceiling mounted gas fired furnace.

Being a remodeling contractor, I wanted to add a little flare to it so I used ceramic tile on the floor and inset a "bird" in the center.

Now just so you don't think that it never gets used as as actual garage ...

My only regret is not using infloor hot water heat and of course not making it twice the size.