[RickFLM4]

Fortunately I haven't needed a body shop often (and hope it stays that way).

The last time I needed one I had an Audi and looked for Audi-certified body shops. Dealers know who they are and they are listed on the Audi USA site. I presume the same is true for BMW and other manufacturers as well. There aren't many to choose from in any particular location, but I would always opt to use a manufacturer-authorized / certified shop so if that would be my first filter. If there were more than one I'd try to find references to pick between them.