The winner is: The Repair Shop. We actually have two of these classic sets, which are better known as Auto Repair Shop Set# 6363. It was off in a corner in the old town but now we're moving it to a more prominent location and, as a result, it needs to look more polished than the rundown building it was before.
Here it is, sitting in its "project box" where I've been tinkering with it. This is NOT the final design, but it is probably pretty close to the overall dimensions and footprint the garage will get. Finishing it off will require the addition of a lot more details to the front of the building to give it some architectural character.
One last look of the "rough draft" of the new repair shop. Check back-- I'll post a new entry once the structure is finished. It'll have a lot more detailing and will probably be taller as getting a 3rd story is a high design priority. I just thought you'd like to see how simple the buildings start out.
Also, you can see the improved Repair Shop in this video: http://youtu.be/zk0-HiyLUoY