Seems that no-one wants to step up to design the garage, so I will offer to be the design consultant.
1.We all know the usual stuff that is must have;
heat, air conditioning, air compressor ... but it must be in a separate utility room (soundproof)
2.It must also have a floor drain and hot and cold running water.
3.It should have a resilient floor because I hate dropping tools or parts only to have them break on concrete.
4.A platter turntable the size of the car to spin it around to any direction
5.A front and rear twin hydaulic post to attach and lift the car, with rotisserie heads to invert the car. Both 4 and 5 by remote control.
6.Must have skylights, not windows. (don't want anyone to see inside)
7.An overhead crane rail and engine hoist (remote controlled)
8.Separate parts department room with every nut, bolt, washer possible for your car.
9.Because the garage must be high enough for all this ... about 16 feet clear... a loft for the bigscreen TV to watch car races, beer fridge and kegs on tap, microwave for popcorn, a computer for research, and a lazy-boy(girl)-recliner for those moments when working on the car becomes too frustrating.
Then you repeat 1 to 9 for the number of cars you intend to park in the garage.
Almost forgot, not attached to the house because it is too easy for the family to come and interupt you. No phone or intercom either, cause they will call you. And of course a bathroom with a shower is a must.
I estimate the whole thing would cost a meager $250,000 (Canadian) per car. Let me know and I will start the detailed construction drawings right away.
And of course there is my fee.