Here is an County of San Diego compilation of affordable homes rules in the area.
Best Practices for Inclusionary/Affordable Homes Rules The County developed this list of programs in the region and the state as they began work on its own policy for increasing affordable homes. Often called Inclusionary housing policies these are very effective means to produce a diversity of housing in a jurisdiction. Consider that 11 of 18 governments in the county have them and when considering the RHNA distribution in the region, the jurisdictions with a mandatory inclusionary housing
program account for 79% of the regional RHNA allocation.