Pet stains on carpet. Use vinegar and baking soda. The steps are important. Pour enough vinegar to soak the stain & THEN add a small amount of baking soda. If you do the reverse, you will have a noisy, bubbly mess. Do it the right way, & you can hear the recipe cackling away, telling you how it is cleaning and deodorizing without leaving any residue. Let the spot dry for a day or two before sweeping up and then vacuuming. Cover the spot with a bowl or plate. Works on old stains too!