A word or idiom for a car mechanic that rips you off

I'm curious if there is an English word or idiom specific for a car mechanic that rips you off. In the case of a doctor, one could use charlatan, or quack.

Bodger — ODO

UK informal A person who makes or repairs something badly or clumsily.

Cowboy — Cambridge

UK informal A dishonest or careless person in business, especially an unqualified one.

"cowboy coach firms are alleged to have flouted safety rules"

An example can be seen on The Guardian "Round up cowboy mechanics, demands consumer body"

Mickey Mouse

adj.

: not deserving to be taken seriously : having little value or importance

M-W

Substandard, poorly executed or organized. Amateurish.

Who's in charge of this mickey mouse operation, anyway?

Urban Dictionary

Elkhart Lake — A racing school is a fantasy land business that leaves no room for Mickey Mouse mechanics or Goofy actions.

The Milwaukee Sentinel

fly-by-night

: given to making a quick profit usually by shady or irresponsible acts

M-W