This would make sense, sort of, if you already have established a customer base. That begs the question if your answer is "yes", just how did you get this customer base?
OK, ethics aside. What is your motivation for an appointment only operation? You don't want to work unless you have to?
I don't want to be mean, but why on earth would you want to turn down work from the retail trade?
My thinking is this, if you have to spend the money on equipment, adding a store front would not cost all that much more. You could have your commercial accounts but you could also be getting the retail accounts as well, which by the way, can be very profitable if done correctly.
I have found over the years that for some reason, when commercial sales drop off, retail sales seem to pick up, and visa versa. Putting all your eggs in one basket just plain doesn't seem prudent to me.
I know there are a lot of shops in California that are very successful at doing just that though. As a new start up , I don't think I would want to risk turning anything down.
Like I said, if you already have the customer base, then go for it, should work out great for you.
John