I saw property values take a hit in Marin in the early 90s. Don't know about the other areas. They don't let people like me near La Jolla or Carmel...
Property prices on the Big Island went down in the 80s. According to friends who sell property, way down, when a lot of Japanese who had invested in real estate bailed out.
BTW, three friends in Sacramento who sell real estate are not making any money. One's going back to her previous profession, one's just broke and has another job. They all got in a little late. One told me yesterday that there are so many houses on the market that nothing is moving, prices haven't dropped a lot (price reductions are happening) but more and more houses are on the market, just sitting there.