Nice garage, BUT I think you will find it is not deep enough. We built our a free-standing (IE, unattached to the house) garage on a city residential lot, but because of power lines in the back of the lot, we had to reduce the depth by 3 feet due to utility easement access required by city ordinance. Doesn`t sound like much, until you start "accumulating stuff" over your lifetime. Most individuals will lament of not building their garage bigger over time. But we all have limitations, either because of cost constraints or building design I(like a pre-package kit) or lot or land size.
One suggestion. Consider running 220V electrical service lines out to it. Why?? Like Tim the Tool Man Taylor says, "More power! Oh, oh, oh, oh, oh..." You never know when you may want to add a welder to your shop or "other" power tools. Or an air conditioner.
The other suggestion?? Consider having at least two fan-powered vents (not just natural air escape) in the roof line IF you are not going to add air conditioning anytime soon. Makes cooling the garage more feasible in the summer time. Chances are you will probably have the garage doors shut while detailing to keep outdoor lawn and tree debris out while doing working, so a little cooler garage is nice to have.
I also assume you did not add a floor drain because of local ordinances/building codes did not allow it or the cost to comply with those codes would have been cost-prohibitive, like the requirement of a grease and oil trap or having to connect it to a municipal storm sewer that is some distance away. I wish I could have one or two in my floor for indoor washing , BUT it was ordinance-prohibited period (unless you wanted to go before the city board , ask for ordinance variance, and prove you had the oil trap and lines to the storm laterals installed, which would have doubled the cost of the garage, plus having the system inspected by the city at their ever-increasing inspection fee every year AND having the trap emptied by a EPA-DNR certified oil recovery service!)
