To the best of my knowledge NO state requires that a landlord change a carpet simply because an animal DID live in the unit. However, if there is an odor, from potty accidents or simply a "doggy smell" from coat/skin issues, an intelligent landlord would at least start with having the carpets professionally cleaned to try and remove the stench! The pro's and con's to this: (and I have personal experience with this because 1. I am a landlord..in San Diego, CA. and 2. It's recently happened to my rental, bedroom carpets/pads...because I do allow pets!) You can professionally clean the carpets, but, if the floors are WOOD under the pad they can not saturate the area being cleaned, it can damage the wood flooring. If the floor is cement, they CAN saturate. Also, when they are cleaned, the smell may appear to be gone; however, it can take up to SIX WEEKS for the smell to COME BACK if 1. they couldn't saturate, or 2. it's totally in the pad or 3. you are having a run of really rotten luck! <wink> As for who pays, well I allow pets, because I believe people have a right to enjoy the company and love of their animals. I train dogs and horses, I have dogs, cats and birds...I'd be quite an ass to deny someone having THEIR beloved companion animals. However, it states in my Rental Agreement that if you have pets (and it says if you do or do not, how many, and their species and names) YOU are responsible to cover ANY COSTS I incur as a result of you, your pets, your visiting friend, or their pets being in/on the property! I do not charge a Pet Deposit. I charge a $2000 DEPOSIT period. The Agreement also says that if the damages are more than that, you need to pony up, or be prepared to go to court, because I'm not paying for your mess! One important thing to remember is that if you want to try and fix the problem with cleaning first...CHECK OUT how long you (the landlord) has to PROVIDE RECEIPTS AND /OR deposit monies...this can vary from state to state! CA only gives 22 days to provide receipts which will NOT help you if you are trying to fix the problem for the least amount of deduction to your tenant's deposit. I would need something in writing FROM THE TENANT agreeing that they will wait to receive their remaining funds and the receipts for SIX weeks, in case I still have to replace the carpets and pads! I just had this very issue with the last tenants...I was willing to inconvenience my NEW tenants, (who were very nice about it)and try to only spend $100 to clean the two bedroom carpets...IF that would solve the problem...the tenants leaving became so nasty about it all that I ended up feeling pissed off myself and said, "fine, forget trying to save you money, you don't want to wait (they said they would sue me, then they said ok do that, then no, then yes, then yes, but will will sue you if you don't have all the receipts to us in exactly 6 weeks), I'll just REPLACE BOTH carpets and pads (estimated cost $800) and send you the $100 it would have cost to clean them. I did luck out and found new for $678.90, less $22.00 that the new tenants had spend renting a Rug Dr...that did NOT solve the problem. I sent the old all of their deposit excepting the rug, the damage to the yard, and the damage to the heater cover (knocked off, evidently when they were moving out) Last word from them, was that they plan to file against me in Small Claims...so we will see! (I had already returned $800 of their deposit to them while I was researching the whole carpet/yard costs, because I felt I could do the repairs for the amount or a bit less than I had estimated off the top of my head and I didn't want them to have to wait for th bulk of their deposit. Opps...I almost forget...VERY IMPORTANT: The Landlord can ONLY charge what the costs would be for LIKE KIND replacement carpet and padding...IF the landlord or the new tenant wants to replace with a better quality or special type of carpet (other than a color change) then the New Tenant or the Landlord would need to pay the DIFFERENCE in cost for the upgrade...you do NOT charge an out-going Tenant to up grade your carpet or padding...that's usually a law, and morally, it would be BAD KARMA to try and stick someone with that!