[timtran303]

I don't think you should be thinking about factories just yet. There is an ecosystem around startup hardware makers. For custom parts, you can order 3D printing shops, or better, buy a 3D printing machine if you have the money. For parts that are metal, get a machinist, or get the machines yourself if you plan on rapidly iterating (manual mill/lathe machines could do most thing. CNC if you could afford it). If you make electronics, there are plenty of PCB prototyping services nowadays, where you send in a design and get a few boards to test. A good side effect of doing it this way is you have total control and ownership of your product, no single factory owns your whole production line. And you don't need to order 10,000 for them to pick up the phone. I'm a software engineer but have always been interested on how to make physical stuff, and I tinker with Arduino, Raspi etc projects regularly. Just my 2 cents.