I started out doing "side jobs", during evenings and weekends, while I was still working for Motorola. I wasn't constrained by any non-compete agreements since Motorola concocted those ideas after I had been employed there for several years. When they did broach such documents I refused to sign.
Beware, you may not be so lucky. Although many states have recently negated the legality of non-compete agreements.
They're everywhere, worldwide, most all of them were referred by other clients.
No.
Yes.
I tried that a few times... yield was about 0.1%, so I rely entirely on word-of-mouth.
Not at the moment, though, now at retirement age, I'm contemplating a few standard products, perhaps aimed at the "audiophool" market ;-)
Plan on starving for a minimum of three years. And starving during portions of the business cycles.
...Jim Thompson