You probably already know this but the rule of thumb is one litterbox per cat plus one. Clean them minimum twice a day, totally empty them out and clean them at least once a month. I prefer to keep litterboxes out of sight. I'm fortunate to have a basement so that's where they're all located, all 8 of them. I don't allow my cats to have total run of the house so I don't really have the problem of them peeing on beds, clothes, in the bathrooms, etc. And they have their beds, I have mine. However, cats are independent little buggers and they hold grudges. If I see one doing a revenge pee, I yell 'NO!" and if I have the squirt gun on hand, I squirt the offender right in the face! And s/he gets banished to the basement for a while. Cats can be trained but it takes longer than w/dogs and it definitely takes more patience. Mine are pretty good but I do have some sneaky pee cats and I don't take chances w/my furniture and my house. They're on medication for behavior modification and as long as I don't miss a dose, their behavior is good and they don't pee. Good luck.