Had a garage do the "duty of care" thing a few years ago when my wife went to pick up our car after a clutch change (I'd dropped it off but then had to go on a work trip abroad). The list of "dangerously worn components" they reeled off made my wife scared to even go near the car in case it spontaneously burst into flames! They told her they couldn't, in good conscience, let her drive the car away without having the work done (and obviously had a quote for the work ready).
When she called me (at the airport) in tears I called the local garage that we'd used for years (unfortunately due to the clutch going just before I left the country they couldn't get me in in time and so, as I wanted the work sorting before I left, I'd been forced to go elsewhere). John "our mechanic" drove to the other garage in his recovery vehicle (expecting to have to tow the car) but after listening to the list of faults he recognised a couple of components that he remembered changing recently (including the brake discs). Anyway, long story short, with the exception of a CV boot that was split, non of the other work was necessary and the car, far from being the deathtrap that it had been described as, was in fact perfectly roadworthy!
This all happened quite a few years ago and I regret that, as I was out of the country for 4 months, I never took any action against the rip-off merchants at the first garage. I like to think that garages are better regulated now but I still cast a critical eye over any quote I get just in case.