Potty train your cat
It may sound — and look — a little ridiculous, but training your cat to use the toilet instead of a litter box can save you a lot of money. The average cost of litter for one cat is $110 annually, according to peteducation.com, and with the average lifespan of a domestic cat being 15 years, you're looking at a total litter expenditure of about $1,650.
Teaching your cat to use the toilet is a fairly simple process, and the cost of a kit is just $20 to $30. The only downside is that you can't teach a cat to flush.