I don't know if the parts are the same as on a diesel but I replaced the clutch slave and master on my old V8 Discovery and it was a bugger of a job, especially the master cylinder as I couldn't get the old one off the fluid pipe as the pipe had flared inside the master cylinder body, making the end too big to come out.
I don't know if this is common but it is the sort of thing that a mechanic has to take into account when giving a quote.
Not defending mechanics but if you take you vehicle to a mechanic instead of doing it yourself and they do a proper, professional job then paying for it shouldn't be a problem.

