Want a cheap litter box where all the corners are rounded and easy to scoop? Concrete mixing tub from the masonry department of your local hardware store. Typically 2 sizes <$10 : r/Frugal
37000 - Cat Love Power Mix Clumping Silica Cat Litter – 3.62 kg (8 lbs)
Amazon.com : HONEY CARE Petrichor Mix Cat Litter I Tofu Cat Litter I Nature Plant-Based Pellets and Bentonite Sustainable Cat Litter I Low-Dust Qucik Clumping Superior Odor Control, 6 Lbs : Pet
Amazon.com : pidan Mixed Tofu Cat Litter - Dust-Free, Fast Drying, and Flushable Clumping Cat Litter - Unscented Kitty Litter for Odor Control(5.3lb×4bags) : Pet Supplies