It's very difficult to remove the odor. Try baking soda with a bit of water. It will help with the smell. I have one timid cat and she continued to go outside of the liter box until I moved it to a new location. She prefers a private location and one that she can escape from quickly. You may need to move the liter box or purchase more and place around your home. It isn't fun but you should be able to tell more by your cat's reaction and what box he/she prefers. It helped me a great deal. She decided where she wanted her box so I removed the others. Also, the type of liter box is a big deal to many cats. You may need to try different designs. The tv program My Cat From Hell (awful title) has great tips. Check out YouTube. Good luck and don't give up. You will figure it out.
I wish I would stop getting asked questions about this place. I had a negative experience there and already wrote about it.
Urine Gone
Oxy clean
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