I’m thinking about moving to somewhere along the Pacific Ocean, but am concerned about corrosion damage to a '74 German car (rust-proofing was an alien concept to them then), as well as a couple of older US made cars. Can it be prevented with proper care, or is it inevitable?
How close to the ocean do you mean? If you’re thinking of moving to Pacifica or Gualala, or someplace like that, then yeah, your machine is toast. I lived in Pacifica for 4 years, with my motorcycle parked outdoors (no garage) – it never looked the same (OTOH, it still runs great at 98K miles, although I did have to replace the exhaust pipes).
I don’t know about parts further North, but here in southern California, rust is not really a problem. The roads are never salted. As long as you keep your car reasonably clean, you should be fine. There are more rust-free antiques on the roads around here than anywhere else in the country, I think.
I lived on the coast (Carlsbad CA) in the mid 70s for several years. I cannot say what rust you may experience but I know that the window seals on our cars deteriorated fast. When we replaced them the repair shop told us this was common when living close to the beach.