Well, my post won't be quite as chock-full of hard-earned info as JAA.
I stopped answering questions about price on the phone a few years ago. I found that it was either a price shopper calling or it was my competition. Either way I didn't want them to have a number they could hang me from.
That being said, if I get someone on the line who would continue to ask me probing questions about my business, I would happily feed them all kinds of bogus information about my business. It's to my disadvantage to give you any real information.
About the only way you could gather all that info is to pretend to be a potential customer and call out every local company to come out for a bid. And this would tie up so much of your time that you'd be better off spending the time pouring over your own numbers to see what you need to charge to make the money you want.