My cat has tortured me for over a year by peeing on the carpet at my front door. I hadn't cleaned it and cleaned it and cleaned it with all sorts of products and methods and nothing was getting rid of the smell or stopping him going there. I could ignore it no more and I had to rip up the carpet last weekend and dump it. I have ordered new vinyl flooring. But the pee was in the concrete flooring. I saturated the floor in white vinegar and let it dry out overnight then saturated it in two full bottles of simple solution cat odour remover and again let it dry over night. It didn't work. The smell was still there and he kept on peeing on it. Then I got this stuff and once again saturated the floor with another two bottles of the stuff and left it overnight to dry out. The smell is gone and the cat hasn't gone near the door since! I'm going to get some more and keep spraying it on the floor to deter him from it as I know they can smell what we can't do maybe there are traces left.
If anyone has any other tips to keep him away from it I would be more than grateful. He has a litter tray in the bathroom which I completely empty every single time he goes in if because he won't use it twice! 
(will use the carpet twice though!! 
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