When Alpha was ill, and didn't make it to the box more often than making it to the box, I had a crash course in learning to eliminate cat urine stains and odors. Because we know you want to do everything you can to protect your security deposit, we wrote this up to help you eliminate any problems that there may be in your home. If you are assuming that the professional carpet cleaning crew can get out the stains and odors out without any effort on your part, I have to be the bearer of unwelcome tidings. While their chemicals are good, they can not leave the enzymes on long enough - the time it takes for the cleaners to do a carpet may allow the enzymes to work on a fresh stain that hasn't soaked into the pad at all - but the enzymes don't have enough time to work to eliminate any old stains - old stains as being more than 48 hours old (in other words, thoroughly dry)
This procedure does not follow the manufacturer's instructions - but it works really, really well.
1) Get one of the following enzyme products - my favorite is Nature's Miracle, the second favorite is the ìhouse brandî of Petsmart called Petzyme. The flowery smelling stuff that Wal Mart and K Mart carry called Out works, but not as well - it will probably take 2 applications, if not 3. I get the enzymes from a pet store, or Petsmart in Paducah or Fairview Heights. They are available on line - but I haven't needed to order that way, so I have no experience with how efficient the Petsmart website is. I also would be concerned about the product getting too hot in transit - enzymes do have a limited temperature range and I'm not sure what the upper range is.
2) Assuming that you have blotted out as much of the stain as possible before you started this procedure, you need to saturate the entire stained area with the enzyme product. As it begins to work you will notice a definite change in odor. Cover the area with a white or clear plastic bag (I use a kitchen trash can liner and weight the edges down to keep the curious kitties away!) You want a white or clear piece of plastic with no printing on it, so that no color will transfer from the plastic to the carpet. Let the area soak for at least 8 to 12 hours. Check to see if the enzymes need to be refreshed - you may need to add more if the stain was large - basic chemistry - as the enzyme is used up in a reaction, it must be replaced for the reaction to continue. I try to soak an area in the morning, check it before I go to sleep, then proceed to the next step the following morning.
3) Rinse the area with lukewarm water (we use a home carpet machine - it makes this easier). If you are doing this step without a carpet machine, step with all your weight on a clean white towel over the stained area and the water will come up. Continue doing this until no more water will come up. If you don't have a white towel, you can place a plain white paper towel (no design) between whatever rags you have and the carpet. It's the same theory of not putting any color in contact with the enzymes and carpet.
4) If the stain is more than 48 hours old, we mix up OxyClean in this manner and apply it - Mix in a separate container 1 to 2 scoops and a pint of very hot water; after the crystals have pretty much dissolved, add cool to lukewarm water to make 1 gal (an old milk jug works well!). Either apply it with a carpet machine and let it sit for an hour or so, or apply it by pouring whatever amount you need to saturate the stain and let it sit for an hour or so. (We mix up a gallon because the carpet machine works well with one gallon of solution in it - you will probably need less, unless you have several stains.)
5) Rinse the area again - in the same manner as you did to get the enzymes out. (Step 3). Turn on a fan, if possible, to help it dry and then vacuum when dry.
6) With a little bit of luck, the stains and odor are gone! If not, repeat the procedure and use more enzymes.
We have found that the Resolve with Pet odor eliminators works well if the kitty has scooted across the floor and left that charming brown line - it also works well if your kitty has been nibbling the plants and upchucks or for the ever popular hairball (we use it on upholstered furniture as well as the carpeting - check for testing instructions.). It is most important to follow the rinsing instructions. We don't find it particularly effective on stains that penetrate.
If you have found another method that works well, please let us know - we'd like to add it to our repertoire.