[nvr2fst]

To make more money you need to do more work, to get more work comes with pay out for more exposure, more work comes with hiring more guys, which comes with more added bills. Its all about passion, if your in it for the funds only then you might as well open up a collision shop. If you have a great reputation and can charge a little more than your competitor most likely your not bringing in more income. A more reputable shop will have larger overhead, higher skilled employees which means higher payroll and more taxes due to the added income. It follows same suit for pretty much any company that does labor contracting.
A consumer most likely will always question the hours and always assume that it shouldn't take that long. If by chance you give the client a bid up front based on the work to be done, you would be pricing it so high to cover your butt just to make sure you don't lose and the consumer will think your out of line.
Your profit is based on payroll only. As Rodger stated earlier, production parts, t-shirts, etc will bring in your additional income but you need that "status" for people to buy your products.
Although Im in the construction industry, an example of a 70.00 rate with the average employee at 27.00 after all expense contributions have been paid the profit would be roughly 18/19% which is 12/14per man hour. This is based on corporate WI. and a very large overhead. When you achieve the 28% tax bracket on income it gets worse.
Keep in mind no matter how many employees you have, they will make mistakes now and then. You can not bill the customer for redo (ethically) and in the end, it's your company, your reputation and your mistake.