i work at a ford dealership and when a customer drops a car off for service, they approve a limit to be spent and sign for that limit if it goes that high, but they reciever a writen quote of what the expected repairs are going to be, and if they are going to be more, the work will not be completled untill service rep calls customer and verifies that its okay to spend more money to have the vehicle fix for however many more flat rate hours. the tech is requesting..motorsports dealers are the same way....there quotes have to be ina certain range and without customer consenting to additional charges its illegal. usually you sign a piece of paper when dropping it off stating what there "spending limit" is i guess would be the best word for it. i know at ford Dealer, anytime customer drops car off with problem, they have to sign off for the 1st hour of diagnostic labor at 84$ just to have it looked at, then rep calls customer requesting more time for the actual repairs