I don't like a cat box inside either, so we cut a hole in the bathroom wall, installed a cat flap, and built a little outside cat bathroom for them to use. Might not be an option for you, but it has worked great for us.
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View from inside in the little half bath off the garage. It's the only counter in the house they are allowed on. I feed them there so Scooter can't eat their food.
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CAT LAX works for Hairball Henry. It's like the old Petromalt. Get it online for about $3-4. Vet's office charges $8.
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