My boss has a saying, "a customer is only concerned about three things, price, quality and delivery. The problem is, you can never give them the price they want, but if you are diligent, you can give them the quality they want in the time frame they are allowing."
WE work some pretty high end stuff, so maybe this will not be of help to you, but our company does not bid anything. Every boat we build is cost plus. They figure a boat will cost 10 million, they add a million on for profit and tell the customer anything over this price and they pay shop rates, material and overhead. This business model does chase some customers away, but ultimately the boat yard's reputation is growing and as a company we really work hard on the quality and on time delivery. As Paul said, there is no need to be concerned with the price, someone will always beat you on that.
I have no intention of traveling from birth to the grave in a manicured and well preserved body; but rather I will skid in sideways, totally beat up, completely worn out, utterly exhausted and jump off my tractor and loudly yell, "Wow, this is what it took to feed a nation!"