That's right, Vinegar to the rescue once again! This inexpensive miracle product is by far the best at tackling tough cat-related odors.
In a spray bottle combine 2 parts white vinegar and one part water and spray over the affected area and wipe with old rags. Sometime I even dump straight vinegar on the problem spot if it is still a problem.
The biggest mistake you can make, and many people do, is attempting to clean cat urine with bleach. This only exacerbates the problem, since the bleach brings out the strong ammonia scent in the urine.
In addition to tackling the smell, the use of vinegar also deters cats from returning to the same spot and spraying again. I have a veritable cat-colony in my backyard, so trust me on this one, it really works!