I'm building a new house now and the one splurge I added to (above) the garage was a small space in the attic with soundproofing to house the air compressor. I'll then place retracting hoses in a few key spots. I like having compressed air readily available, but I'm not a fan of the noisy compressors. A little wood, some sound proofing insulation, and a bit of extra tubing are all pretty cheap and well worth it to me.

Some other things I have seen... if you want to add storage above the garage, you might consider either doing a real set of stairs at the back of the garage to make it more accessible and/or a motorize storage lift system that essentially serves as an elevator for lifting your stuff up into the attic. And shelves within the attic are always useful.

Finally, consider adding 220V electrical wiring to allow an electrical car charger in the future. It is always better to have it and not need it than to need it and not have it.


EDIT: This is likely a good place to ask. Does anyone know of a good boom arm solution for compressed air? I'm basically looking for a good solution where I have one or more hanging air lines and I can grab one and walk to any tire position and the boom arm will swing directly overhead so I don't have to mess with yanking hoses around on the floor and where it will just go back to its home position afterwards and not leave a wad of hose on the floor. Surely these types of solutions exist for garage bays. Does anyone have any experience with such a thing or have any advice regarding a provider?

 

I second the idea about a fan of some sort. An exhaust fan won't make a huge difference in cooling if you're in humid, tropical weather, but it will move out the engine heat and keep things from getting too stagnant.