Legal Question in Landlord & Tenant Law in California

It's called free enterprise. It allows rents to be adjusted based on market conditions. Tenants are allowed to leave under the same notice conditions. If a renter wants more security for the long term, they can enter into a lease for a long term.

You are looking at section 827 backward. The right to occupy real property as a tenant is a matter of contract. When a contract ends and the parties want to continue or renew it, any and all of the terms can be changed. If one party doesn't agree to the other's changes, there is no new contract. In that case, in the landlord/tenant situation, the tenant must leave. That gives the landlord the right to raise rents any time and by as much as they want, as long as it's effective at the end of the lease term. Section 827 didn't create that right. It's basic contract and lease law that has existed all the way back to the law of England from which we took our basic legal system when the U.S. was founded.

What section 827 does and the reason it was passed is to protect tenants from surprise rent increases in month to month and other short term leases. Prior to the passage of 827, a landlord could drop a surprise rent increase on a tenant at the end of any month or other short term renewable rental period, with no warning. It was pay the new rent or an eviction action could be served the next day. Section 827 provides protections from surprise rent increases by requiring 30-days notice for month to month rent increases of less than 10%, and 60-days notice for increases that either by themselves or cumulatively in any 12 month period amount to a 10% or greater increase.