From City of Carlsbad Inclusionary Zoning Bonus - "One way that developers of single family homes can comply with the city’s inclusionary housing ordinance is by constructing ADUs that have a deed restriction. The deed restriction lasts for a period of 55 years, and requires that rent for the ADU be restricted to a low income level and that tenants be income qualified. The city’s inclusionary housing ordinance is a part of the zoning ordinance and applies to residential projects of seven or more units." Source: https://www.aducalifornia.org/best-practices/