How do you know if you’re pricing your product correctly?

When it comes time to price a proposal or product, how do you decide the amount to charge?  You of course want to charge enough so that you will make a profit.  The trick is how to determine what that amount should be.  Are you able to evaluate the time and materials that went into previous products so that you know your “break-even” point?  Do you have a way of tracking the time you spend on the various parts of your business?  There are lots of solutions for tracking both time and materials that can help you to be sure that your pricing is on target!