I think you are missing my point. The standardized labor figure should be easily found my anyone competent in this busines. Not everyone follows the book, but that wasn't my discussion.
My point is that once you have decided to buy that 120k service that is figured at say four hours labor at both places and the same parts and the independent is 50 dollars cheaper. It should be because he is slightly less on the labor rate and maybe a little less on parts.
THE DIFFERENCE will come by how each shop pays his help (this might be considerably different in U.K.). The one that pays by flat-rate is giving his crew the incentive to work fast, cut corners, etc. The one that pays hourly (basically salary) gives the tech the right to be meticulous. His only incentive is his desire for beautiful work. One tech will do three or four of these services a day the other one and a half. My shop pays hourly, ask how I know how many four hour services, techs under this system, can do in a day.
If a flat rate tech makes a mistake he will have to work for free the next time. In my shop if a car comes back it might not even go to the same tech as the new problem might be better approached by a different tech with different skills. Under our system work is the same whether it is come back or new. No body works for free. The customer of course does not pay.
This single issue is the number one reason I guarantee that any shop you go to will have an average seniority of less than five years (if they PAY flat-rate). Our seventeen employees average over ten years seniority AT OUR SHOP (not just in the industry).
BTW. It isn't necessarily the dealer who will pay flat-rate. Most shops historically have paid flat-rate in the US. You will very seldom find a heavy truck shop that pays flat-rate though. Would you want your doctor to be paid flat-rate. Its sure good they make so much money the incentive isn't as great as we Americans probably all pay flat-rate to our doctors.
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician