Engine overhaul

I have a friend who is rather upset over the fact that his car went into the garage for rectification of a supposedly small problem and came back with a huge bill for an engine overhaul.

I asked him what had gone wrong with his car and what work had to be performed as part of the engine overhaul.

"I don't think you understand," he said. "You see, 'engine overhaul' is not a category of work. It is a category of bill."