I dropped off my laptop with display errors and crashes, they replaced my screen's glass front insisting that this would solve the problem. Obviously, it didn't. Instead of charging me £198 for a useless 'repair' they offered to replace my original screen. They had apparently chiselled it off (instead of softening the adhesive and pulling off the glass, as the briefest of searches will suggest to do), smashing the glass all around the frame and even damaging the plastic rim around the glass.
Looks like either they wanted to charge an outrageous price for the simplest repair and hope for the best or there was poor communication between the shop and the mechanics.
During a lengthy argument they admitted to causing the damage but refused to repair it and said that I had to take them to court to claim back the damages. The case has been filed, I'm awaiting a response.