Finally a welcoming backdoor and the kitty pee smell problem solved
Big thank you to Anna for all your help in figuring out this system. Anna suggested cotton mats as being a material cats won’t pee on. I also sprayed them with vinegar which is meant to discourage them from peeing.
After almost three years I finally have a solution to make my house not smell of cat pee and to have a welcoming back door. Thanks also to Monique for the shoe rack and for Leanne to introducing me to broom grabbers. This all means a huge deal to me.
So far the cats are still peeing on the mat closest to the door but at least it’s very low stress to clean! More iterative attempts at solving this is required.