My cat must now stay in a cage most of the time as compared to being free as an indoor cat since I moved homes, so now I am back to using his metal basin for my cat to pee in while he is in his cage. So now I wonder if you are using or have thought of using a plastic or metal basin for your cat to pee or poo in? I never owned a litter box so I have no idea how much you will get to save if you just use a basin.