How rent control passes (or doesn't) to new roommates
Rent control is usually tied to a rental unit and tenancy rules, not a simple promise that every future roommate inherits the same deal. Whether a person replaces a departing tenant, becomes a co-tenant, rents from a master tenant, or enters a new lease can matter.
Before moving in, ask who is on the lease, what the total lawful rent is, whether the landlord approved the change, and how your payment was set. Obtain written terms and save all notices. Do not rely on a roommate’s verbal assurance that “the rent can never change.”
For a pending replacement or rent increase, ask the Rent Board to explain the current local rules for your facts.
Source: SF Rent Board.