I am a full time builder and have been since 1989. I worked for other builders until 2003 when I started my own company and have been busy ever since. I would not call this a get rich quick scheme but at the same time I'm comfortable, eat well and take a vacation every year. I think the term "middle class" might fit.
I have a few things to keep in mind about framebuilding as a business -
* I often read that there are builders out there with long wait lists therefore there must be a pent up demand for handbuilt frames............so......... it must be a good time to throw one's hat into the ring and build/sell handbuilt bikes to satisfy that demand. I think this is a misinterpretation of what is going on. I don't think that Vanilla has a multi year wait because there is a great demand for a well built handmade frame but instead I think it shows that there is a demand for Vanilla's. There is a big difference. If Vanilla's demand was created by overall demand for handmade bikes then we would see many other builders with similar demand - but we don't. So starting a business to take advantage of this perceived demand can really ruin your day when the phone doesn't ring. Unless you are going to make Vanilla's you won't be directly addressing the demand.
* Framebuilding is a fun business to be in but at it's core it is a business first and foremost. By this I mean that the f-building is just a small part of the deal. I spend about 1/2 my time at the bench and the other 1/2 doing everything else. The 'everything else' is the wild card in my opinion. The framebuilding itself is the straightforward and frankly easy part and the rest of the stuff is what makes or breaks the deal and puts the business in the red or the black. Customer service, design, fitting, ordering, accounting, time management, inventory control of both raw materials and finished goods, cost control, sales, marketing.............these are just a few of the things that need to be attended to if one wants to make a living. The builder needs to wear lots of different hats and each one of those hats is equally important to wear well. By that I mean you might be able to lay the perfect 'roll of dimes' TIG beads but if you can't manage your cash flow you will not make it as a business and turn a long term profit. Perfect lug shorelines will not in any way guarantee the builder will turn a profit. A successful builder will be good at all the above and more.
* I think it is extremely rare that someone who is still working on their basic building skills can somehow make a business out of it. I think the builder should have building down cold long before they hang up their shingle. That brings the inevitable question of 'how many bikes do I need to build before I'm good enough?' I wish I had an answer but I don't and I doubt that anyone does. Different people learn at different rates and some are pretty darn good with not that many bikes under their belts and others will need many, many more. That said, and having taught many people to build at a professional level, I feel safe in saying that having 10 bikes out there will not make you an expert builder. When I started building it was in a factory setting and we built more bikes in a day than even some pro builders do in a month or year - so lots of bikes passed through our hands everyday and we got lots of practice. For instance I brazed 5-10 bikes a day for months on end and frankly got good at it. I recall that after I'd been doing this for a year and had built or worked on hundreds of bikes that I thought I was the **** and that there was little left to for me to learn. I was very wrong. Maybe I was a slow learner - I don't know. But even though I'd worked on so much stuff I was not ready to be on my own and do pro quality work. So when I read that someone has built 10 bikes and none have broken so they are ready to have their own business I have more than a bit of skepticism. Now, all these years and many thousands of bikes later I'm still learning. The learning curve is flatter that is was way back when but it's still there and the more I learn the easier it gets to make a living at this.
I guess I would summarize this overly wordy post by saying that liking the act of framebuilding itself may not be a good reason to jump into business. If you are a skilled builder (or in time will be) and are interested in the business of framebuilding then I think it's worth thinking about. If you love building but dislike the idea of spending 1/2 your time balancing the books and returning customer emails then maybe you want to be a hobby builder. I do not think the term 'hobby' is a bad one and do not mean it as an insult. I think doing this as a hobby would be really fun and a great way to express yourself.
I do not want to discourage anyone from jumping in to the business but instead I'd like to think that everyone that does has their eyes wide open. I think we would see far fewer builders go under if that was the case.
All the best,
Dave