I decided last night that I am going to rip out the carpets in my place!!! Layla has been having accidents again. We left her home on the weekend, with my brother coming over to feed her, let her out, and play with her for awhile. But when Scott and I got home yesterday we found 4 pee spots. I asked him to bring me the blacklight after I had put cleaner on them because I couldn't see where the last spot was. I haven't used the blacklight in my new place yet... well all I can say is
The carpet is a light color and everytime Layla pees, I can see the yellow spot. After cleaning it, the spot is gone. Well, the old owners didn't have a dog but they mentioned their son brought his dog over sometimes. I have a feeling that dog has peed on the carpets too, but the spots were cleaned so they weren't noticeable. They're definitely noticeable with the blacklight

There's no way to get rid of those old spots... and that's probably the reason that Layla started using the carpets too, from smelling the old spots!