This is attorney Bill assisting you today. There may be a slight delay between your questions and my feedback. Please allow me the time to consider the law to give you an accurate answer.
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Under California civil code and nothwithstanding what is stated in the lease the landlord can only enter and disrupt a tenant in a limited number of circumstances.
These are outlined in law , breach of which leaves the landlord open to prosecution in civil court.
Under Civil Code 1954 [see below], the landlord may enter your unit without your permission ONLY:
(1) in an emergency, like a fire or broken pipe, or
(2) upon reasonable advance notice, and then ONLY:
(A) to inspect, repair, or show the apartment,
(B) during normal business hours [presumably Mon.-Fri. 8AM-6PM]
(C) 24 hours is presumed to be sufficient notice
(D) You do not have to be home when they come, but the landlord is liable for anything stolen or broken.
(D) The notice must identify a date and reasonable time range [like an hour] within which the entry will occur
(E) The notice MUST be written [not oral or e-mail], except if a WRITTEN notice that realtors will be showing the property is given, for the next 120 days only an oral telephonic 24 hour notice is required [business hour limit still applies]
(G) The right of entry can't be "abused", so that an open house, lock box, extended repair, daily entry, or excessive range of entry time are probably all "abuses" which you have the legal right to prevent.
Hence these rights are clearly outlined in law.
Your right to refuse is guaranteed if not mentioned in the above quoted statute as a valid ground.
A month to month tenancy gives you the same protections in law in relation to illegal entry by a landlord and the change of your tenancy into this type does not effect your answer.
Please follow up with me if you need more information.
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