Instead of having people buy up the property and jack the prices to shit, just have some notion of "Californian citizenship".
* If you were born there, you're grandfathered in by birthright.
* If you move out, we'll pay you some money or whatever.
* If you want to move in, either pay a big sum of money or convince the government you're helpful.
Then they could use the money from these sales to invest in the community, rather than it going to property speculators.