An Indy is
A shop that specializes in BMW repair but is not a dealer or directly associated with BMW.
Often the staff will be mechanics that have worked at BMW dealerships and the better shops will have sent there mechanics to BMW training schools to keep there knowledge current . So they will have specific knowledge on your car .
Sometime they will do other Euro Cars to.
They will charge you much less for the same repairs than what you would get
at most dealerships.
There is a list of known good ones somewhere on this board I think.