A California landlord can raise a security deposit, within the maximum allowed by law, for a month-to-month tenancy with a properly served written change of terms notice of at least 30 days. For a fixed-term lease the increase could be imposed at renewal, but not during the term of the lease.
If your lease is up and your on a month to month a landlord can increase rent and deposit each month if he /She wanted. If not only when ur lease is up and u sign new one. Hope this helps ...I'm not professional just what i know in CA.
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