In my limited experience already, 8 months, I've come to learn, that with my one machine, the shop rate will vary according to the job. Simple ally work is cheap especially in production quantities. There's no head aches, and tooling is dirt cheap. Some complicated tricked out stainless stuff is gonna work out to more. Quoting jobs is an art. Especially if you are new to the game it's almost a dark art. You can anticipate problems and try to eliminate them before hand.(This is easier when they guy quoting is actually running the job). I worked in a shop where they let the guys on the machines quote to the owners, this way we had an idea how we were going to meet the times.
Quoting will never be an exact science. Unless you are Geof, and develope your parts standing infront of the machine.
It's something that has to be learned. Hell all those high quotes can be from a shop that is too busy to take the work. They don't want to say no, so they price high. Done it myself, and seen some of those jobs. Doesn't work, but then your return per hour will be pretty comfortable.
Like Hu says. When you start out, you will ineveitably take everything that comes your way. While you are paying the bills, find a niche in the market you are comfortable with and go after it. If you aren't setup for full tilt production, then you may want to stay away from things like mass produced bike parts and such. If you have a $1,000,000 FMS(Flexable Manufacturing System), then you may be able to go after that sort of thing cause your man $$$$ are significantly lower.
All I can say is Good Luck with your endevour. And don't get frustrated on here if you are quoting and not getting anything. If you are a shop owner. You are possibly competing with Hobby guys who charge enough to pay for their tools and such.
I've done some jobs through here, and I got them because of my location, simple. I wasn't the cheapest, my shop was the best fit for the customer. And I was willing to take a chance on a kid, that most local shops priced so high it was like a kick in the nuts.