I don't like Nature's Miracle at all. I think it's useless.
To get cat pee smell out of carpet, here's what I do:
I use a inkjet cartridge refilling syringe that came with the refill kits that you can buy at Staples. It is about 10ml volume and it has a sturdy needle on it, too. I read someone say they use a marinade injector, but I don't have one and I do have cartridge-refill syringes to spare.
I use either one of two products, liquids,
UrineOff by BioPro Research (buy that in pints or gallons at pet stores) or
Urine-Away by Ceva USA (smells better but costs more plus I also have to get it from the vet here, if I want a gallon).
Update: http://www.vetrxdirect.com/product/v...ine-eliminator sells the Ceva product by the gallon now.
1. Blot up as much urine as possible. Lay towels on it and newspapers and whatever, and tromp around on it for a while, to draw as much as possible out. That is important to do.
2. If there are stains, like from blood in the urine, I scrub with Resolve and a soft brush. Then repeat the blotting-up.
3. Fill a cup with the urine-killer liquid. Draw it up into the syringe.
4. Depending on how badly soaked the carpet was to begin with, I might go with 4" intervals or I might do 1.5" intervals. But I picture a grid on the floor. And I stick that syringe into that carpet a little so that the urine-killer goes into the jute backing and then down underneath to soak both the jute and the carpet pad underneath. And I inject that urine-killer into the carpet. How much and how closely together is at user discretion. Imagine how much volume that cat put into that rug, and then put that much urine-killer in, will do it.
5. Leave it soak forever and eventually it will dry. It takes some time for it to work, so leave it at least 2-3 days if not longer.
That ought to kill all pee odors within 24-48 hours, so far as humans can tell. I use it as a stop-gap method to just get rid of the flippin' pee odor a) without pulling up the carpet, and 2) until I can clean the carpet properly.
The urine-killer products have their own weird odor. But not as bad as cat pee, and it goes away with time, or immediately if you clean the carpets.
Keep in mind that by the time you notice cat pee odor, there might be a 3' - 4' radius of carpet involved. Get down there and sniff to see how big of an area to treat. Or just go out 4' in all directions, if you are the squeamish type, haha.
That syringe idea should also work for hardwood floors. Work the cracks between the boards and let it run down underneath. How much to use is your decision. Hardwood isn't going to absorb. Naturally, you'd need much less urine-killer than for carpet + padding.
My female cat designated one corner as her pee-corner. I finally got fed up and got a big shock mat (rectangle) and laid it down in that corner. I turned it up all the way and I set her on it, twice, so she got a good jolt. I wanted it to be a real bad experience to be in that corner. I left the mat there. She doesn't even go near that corner anymore. Sounds cruel, I know, but there's nothing medically wrong with her, and she does use the litter box but would use that corner if it was more convenient at the moment. I have scoured the house but I don't find pee anywhere else.