20x24???
I don't know what you are planing to do with it, but a 20x24 is realy just big enough to hold two normal cars. Granted a T does not take up much room, but if you plan to work in it, I would go at least 24x24, bigger if you could swing it. My shop is 24x24. one side is PACKED with my mustang, and two small motor cycles in it. The other is the working side. OK room, but not a ton. Granted my stuff is pretty big, but more room is better then not enough.