Pet Rent and Pet Deposits in California - While some states allow both Pet Rent and Pet Deposits, I have found through my own research (get your own legal advice) that California law does not have enough case law regarding Pet Rent and CA judges may consider Pet Rent as a monthly Pet Security Deposit and that could be a problem if you have a long-term tenant and end up charging more of a total security deposit than you are allowed (two times rent unfurnished, three times rent furnished). And so you may have to return all of that "pet rent." The California Apartment Association does not and will not add a Pet Rent section to the Pet Addendum because of the lack of case law in California on the subject, so common practice in CA is limited to Pet Security Deposits in the CAA's view.
However, all rent and security deposits are negotiable.
So, a landlord may charge a certain rent for tenants without pets. The landlord also can negotiate with prospective tenants a higher rent if they want/have a pet or two, or if they have some other need or amenity they want, such as a refrigerator, or water bed or something. The landlord also can negotiate a higher security deposit if the prospects have pets, and/or some other reason that a higher security deposit might be safer for the landlord/owner.
But, on the lease, the key is the ONLY THING STATED on the official paperwork is the monthly rent price, and the total security deposit. It says nothing about pet rent OR pet deposit or any reason the rent and security deposit were negotiated differently.
Additionally, I'm not sure, but I have heard that a separate Pet Deposit can be determined by some CA judges as a fee that can ONLY be used for pet damage, not for other damage... and proving certain damage is caused by a pet isn't always easy. So, that's another reason you don't want separate Security and Pet Deposits. If you do use both, they can't total more than the maximum allowed by a Security Deposit.
Again, I'm not a lawyer... but I hope that information helps California landlords deal with these Pet issues. And, if there is a lawyer out there who finds something incorrect about what I've learned and mentioned above, please comment on what may be incorrect. Thanks!