Here is the big difference between my car mechanic and my LAME -
I can ask both of them the same question for a quote, how long to replace the exhaust manifold on my - LAME, airplane - mechanic, car.
I get roughly the same answer, 3 hours.
The mechanic got this answer by looking in a book that listed my model of car, and the part that needed replacing and it gave an approximate time for it. He showed me this book, but I can't remember exactly what it was called.
I have no idea how my LAME arrived at this conclusion.
The mechanic had a spare guy standing around, so he helped on the job, and got it done in 2 hours, and I was charged 2 hours for the job and was able to pick the car up on time.
The LAME also had 2 guys work on my plane, at the same time, and charged me 2 X 3 hours for a total of 6 hours to complete the 3 hour job...