"""Can you really justify charging the customer for this lack of knowledge?"""

I often wondered about this, charging for diagnosis, if its a common fault, which you dont know about yet,(and everyone else does, once you find it) If it takes a few hours to find, do you charge them for a couple of hours, or do you charge them for 1 Hr,

Also if a common fault comes in,say escort side lights not working, you know 99% its the switch whats faulty, so do you charge for diagnosing, or just for the parts & fitting

ti
Mick