I have found (with cats) that the best neutralizer is OUT concentrate (both bother with the ready to use). I have used this to totally get rid of urine smells. Even through a mattress and boxspring (my previous cats didn't like that I left them for my honeymoon). You dilute it with warm warm, soak the area, cover with damp towel, let sit for 24 hours, & let dry. Never failed. Don't know for sure, but I think you can use it on the dog/cat. Could her smell be from her diet? With our last dog, improving her diet made a big difference in her body odor. Just a thought.

Odours can building up once a house has been 'closed up' for a few weeks. The way to deal with it = remove carpets/flooring to find the odour and then deal with what you find. The odour will not go away until you remove the soaked products (usually carpets...sometimes drywall...depends on the animal that made the mess) and replace with clean/fresh products. There is no easy fix. The 'musty' smell is from dampness caused by water or moisture promoting mildew or mold growth. This can be easier to find but much harder to fix. Again, the only way to find it is to search for it. Look for 'water stains' on ceilings, in bathrooms, in the basement, under the sinks, around windows, etc. These are the natural places where moisture damage will show up. Can you take photos of any 'stains' on walls or floors or ceilings?

Thanks to all of you for the tips. I'll try the vinegar tomorrow. Pbrisjar--does it matter if it is white vinegar vs. the brownish cider vinegar? I sprayed the floor and all the walls with a peroxide and baking soda solution yesterday (recommended in a thread that I found on the flooring forum). That seemed to help at first, but I think the smell is coming back. It sounds like I will probably have to buy a lot of primer and seal the odor into the walls and/or the floor. I went to petsmart today and bought a blacklight; hopefully that will help me find the worst areas so that I know where to concentrate my efforts. I have a feeling the walls are worse than the floor; when applying the peroxide solution I noticed some discoloration and residue about 2 feet up from the floor on a few walls, so those may have been major spraying locations. I bought a large bottle of an enzymatic cleaner that sounded like it might help with older stains, but it was $35 and I know it won't be enough for the whole area, so if it's not much different from vinegar I may as well return it for a refund. Yes, I'm sure the prior owners knew about it. I have no idea how they managed to hide it every time that I came to the house (I have a sensitive nose), and it irks me that they did. If I'd known, I could have had a painter seal everything before I moved in, while it was still empty. At the closing, the owner mentioned that the cats had been "stressed" because of the move; I guess she knew that I would soon discover the smell. Thanks again!!

Borax is probably more of a problem if you inhale the dust or actually get it next to your skin. Such as rolling around on the carpet, and then only if you are sensitive to various things. I would still want to use a carpet extraction/cleaning machine. Whether you use your own, rent one, or pay someone to clean the carpet, I would still want the carpets cleaned. The borax probably just masks the odors. Doesn't really get the dog pee out of the carpet. If you are cleaning your own, I would suggest checking out to see if you have a janitorial supply company. I buy an odor eliminator and carpet cleaning solution from a local company. It's concentrated and I find it doesn't leave the residue on the carpets like the stuff they sell in the grocery stores.