I purchased a used PTR96 about 4 years ago. I had been laid off (again!) and was sick of it all and wanted to start my own thing. At the time, I hardly knew how to turn on a computer, but I had worked most of my life in the sign business from designer (drafting table) to sales and production.
When I started out, I got a lot of great help from Ron Varela, whom some in here know. I didn't have time to go to school and learn CAD. Ron had me making dust in a few days. There was much to learn, but he was always a phone call away. I'll say that the folks at ShopBot have been great as well. Whenever I had problems with my machine,(there hasn't been many) they have always been VERY helpful.
I am not a sign company. I do CNC work for sign companies that have a need for CNC work. They do all the selling and hassleing with customers then bring me the work along with the materials! (Mostly sign foam.)I built a 20'x24' shop right next to my house a couple of years ago (sure beats renting a shop)and I am exactly 6 steps out my front door from work! I often stumble to work in the morning in my underwear to get things going! LOL! (I live out in the woods and am a "one man operation", so I can do that!):-)
I would say to anyone that is thinking about buying a ShopBot and starting a business this: Have a plan. Know where your customers are gonna come from. Don't think they will just magically appear once you buy your machine. There are many, many ways to make $$$ with a CNC, and signs are certainly one of them, but do have a plan. Once you have that, the rest is easy. If I did it, anyone can, if they want it bad enough!
Tuck