What Mericet said.
I've been doing it as a hobby for 25 years and have only recently started as a serious business.
Black gun, 1911's and Glock building and tuning are what most people are interested in. Plus I have a lot of contacts in the police/firefighter field. I am able to give them better prices than most, because of low overhead, and still manage to turn a buck or two. I have to keep my current full-time IT job for insurance, but more and more they don't like old guys