DEPOSITS
In Oregon, landlords can charge refundable deposits for a variety of things, but they must be REFUNDABLE. Non refundable deposits, along with most upfront fees, are not allowed. There is not a dollar limit on the amount a landlord can charge.
SECURITY DEPOSIT - The most common deposit is the security deposit. Called by a variety of names, it is what I call The Deposit, used to cover damages to the rental property, cleaning costs, loss of keys, and more. An intelligent landlord will have one deposit to cover everything. Some landlords have a cleaning deposit, security deposit, key deposit, and more. One deposit is enough to cover everything (except maybe a pet deposit - more on that later).
The Deposit should be used to cover anything beyond "normal wear and tear." The definition of normal wear and tear? Good question; no good answer. Seriously. Good landlords have an understanding of what exceeds normal wear and tear, and charge accordingly. Some charge for any and everything. Your job is to do as little damage as possible, keep the unit clean, and make it extra clean when you leave. This is the best way to receive some or all of your deposit.
CARPET CLEANING DEPOSIT/FEE - I wrote both deposit and fee for a reason. Under Oregon Revised Statutes, section 90 (THE landlord & tenant statute), it is called a carpet cleaning deposit. However, a landlord can use the deposit just like a fee, using the deposit to clean the carpet for the next tenant, and using the next tenant's carpet cleaning deposit to clean the carpet, and so forth, as long as the rental agreement states this is what will be done.
PET DEPOSIT - Landlords can charge a pet deposit for each pet. There is no limit on the amount. Landlords CANNOT charge a pet deposit for an assistant animal (also know as a therapy, companion, etc. animal). Doing so would be a violation of federal and state fair housing law, and state landlord/tenant law.
HOW TO GET YOUR DEPOSIT BACK - AT LEAST A GOOD PORTION - Before you move in, and again after you have CLEANED your unit when moving out, take photos of EVERYTHING! Start with the front door on the outside, and move inside, going in a clockwise direction. Take photos of every surface, and inside and behind everything (yes, inside and behind the oven and refrigerator). This way you will have a record of what it looked like when you moved in and out. Good for comparison purposes when your landlord doesn't return enough of your deposit, charging you for things that weren't there, or are there before you moved in.
Once you have moved out and returned the keys to the landlord, they have 31 days to return and/or account for your deposit. This means 31 days to put it in the mail (the statute isn't clear on the "in the mail,' but that is how it has been interpreted). ORS90.300 (12) states, "In order to claim all or part of any prepaid rent or security deposit, within 31 days after the tenancy terminates and the tenant delivers possession the landlord shall give to the tenant a written accounting that states specifically the basis or bases of the claim (emphasis added). The landlord shall give a separate accounting for security deposits and for prepaid rent."
What to do if you don't agree with the amount of your returned deposit, the information provided to you is not specific, or what if you don't even hear from your landlord. See the page titled, Deposits II.