Never reveal to a customer the method you used to arrive at the price. Never break down a bid into parts and labor AND NEVER TELL THE CUSTOMER YOUR HOURLY RATE.

No business in the world would provide their customers with this proprietary, confidential information.

There's absolutely no upside to revealing this information, it will only be used against you.

When asked about my pricing, I say that my prices are arrived at by a computer program that updates materials on a weekly basis and generates my prices.

It has nothing to with "being honest" and having "nothing to hide". Would you send the customer your QuickBooks files or personal pictures of your wife? No, some things are nobody's G-damn business but your own.

Sorry for the rant, but I think it's real tacky when people demand to know how much money I plan to make or what my overhead costs are.