Akers in Seattle proper has a good reputation and has been around forever. The prior owner of my Boxster used them.
Aker's Porsche - Porsche, Audi and VW. We do auto repair. General mechanical, transmission rebuild engine rebuild, electrical systems. Repair & diagnostics, suspension repair, brakes, tune ups check engine lights.
2 blocks outside the Seattle city limits to the Northeast in Lake Forest Park is Continental Motors. It is a European Auto shop. I have used them for a coolant drain and fill. Price was decent and the service was good.
https://www.continentalmotorswa.com