In most states, additional "pet rent" is permitted. The Oregon Landlord/Tenant laws can be found at the link below. A review of those laws reveals no provision prohibiting a landlord from charging additional "pet rent."
DISCLAIMER: Brandy A. Peeples is licensed to practice law in the State of Maryland. This answer is being provided for informational purposes only and the laws of your jurisdiction may differ. This answer based on general legal principles and is not intended for the purpose of providing specific legal advice or opinions. Under no circumstances does this answer constitute the establishment of an attorney-client relationship. For legal advice relating to your specific situation, I strongly urge you to consult with an attorney in your area. NO COMMUNICATIONS WITH ME ARE TO BE CONSTRUED AS ARISING FROM AN ATTORNEY-CLIENT RELATIONSHIP AND NO ATTORNEY-CLIENT RELATIONSHIP WILL BE ESTABLISHED WITH ME UNLESS I HAVE EXPRESSLY AGREED TO UNDERTAKE YOUR REPRESENTATION, WHICH INCLUDES THE EXECUTION OF A WRITTEN AGREEMENT OF RETAINER.
Ms. Peeples and Mr. Pittman are correct. Oregon's Landlord-Tenant Act does not allow the landlord to charge a non-refundable "fee" for a pet. ORS 90.530(2)(a) also provides additional protections for service animals and tenants living in manufactured or floating homes, but neither of these help you because your pet is a cat and you live in an apartment.
If you look to the definitions of "rent" and "fees," I think that gives us the best answer. ORS 90.100(15) defines a fee as a nonrefundable payment of money. At first, it sounds like this would cover your "pet rent" because it's never going to be refunded. However, then there's ORS 90.100(35), which defines rent as a payment in exchange for the right of a tenant and any permitted pet to occupy a dwelling unit. Here's a link to those definitions: http://www.oregonlaws.org/ors/90.100
To me, "pet rent" seems like a cute way of getting around the prohibition against impermissible pet fees. However, under the current Landlord-Tenant Act, it's allowed. If it makes you feel better, I'm a Landlord-Tenant attorney and I pay it too.
My responses to posts on AVVO are not legal advice, nor do they create an attorney-client relationship. In order to provide true (and reliable) legal advice, an attorney must be able to ask questions of the person seeking legal advice and to thus gather the appropriate information. In order for an attorney-client relationship to exist, you and I both have to agree the the terms of such an agreement.
It's a dirty trick, but landlords CAN get away with charging "pet rent," as long as they set it up right. Many landlords will probably screw it up, however.
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