A lot of these post have come up lately on different forums.
The best piece of advice I can offer is, if one wants to make a living in gun smithing, diversify.
I had a shop for a while, started out as a hobby, then I started building 1000 yard match rifles for members of the Alaska National Guard Rifle team.
About the same time I saw a friend of mine go belly up, couldnt make a go of it. He was a dern good smith too.
One day I was off work because I injured my hand. I was hanging around his shop when a guy from the auto parts store next door came in wanted 4 wheel spacers openned up .020 for a larger hub. My friend started ranting about being a gun shop and not a machine shop. Good friendly fuss started. While he and the auto parts guy was fussing, I took the hubs, using my buddies lathe, openned up the hubs. The four hubs took me 20 minutes total and I made $20 a peace. $80 Bucks in 20 minutes. My buddy just laughted and said he still wasnt a machine shop.
Later I desided to open my shop, working out of my garage. I put two adds in the yellow pages, one for Gunsmithing, one for Machine Shop. My phone rang off the hook. I did some work on guns, I did a lot of light machine shop work.
There are lots of Machine shops out there, few will take on the small nickle and dime jobs. I did, I was making dern good money that supported my gun hobby.
The problem is, I was working full time, running a National Guard Unit, and raising a family. I ended up ruining a good hobby. I got were I hated to get up. I spent all my awake, not working time in the shop.
I closed up. Firguring I would start up again when I retired. Instead I desided to be retired. I only work on my stuff, build a gun every now and then for my kids or grandkids, but my main hobby now is chasing my granddaughter's basketball/Vollyball teams all over the state.
You need equipment, lathe, milling machine, belt sanders, grinders (polishing and grinding) air compressor, bluing tanks, welders, gas, arc and mig. Not to mention the tons of small tools and gigs, but you can make a lot of them.
If you get started, have the machinery, and skills, don't be afraid to take in light machine work. Guy here in town does light machining. Most of his buisness comes from the larger machine shops. The large shops say anything under $1000 is a small job and wont talk to you. For 15+ years he's been trying to get me to open up to take some slack off him. I don't want to work, I want to be retired. Still neighbors bring me projects.
The name of the game is DIVERSIFY. As you progress, if you do good work, and provide good service, your gunsmithing will grow. Until then machine work will feed your family.