First time cat owner

VMR

Any tips? I’ve had them for about 1 week now and things are going great. They’re 2 years old, litter trained, sooo friendly and loveable

Previous owner said they HATE water, so how do I make sure they don’t smell/stay clean? I know of no rinse shampoo, would that be enough?

Also, how do I keep the littler box odor down?