The hidden litter box certainly looks good, but doesn't it get smelly?Remember that special toilet seat for kitties? That was a good one too, provided that the kitty learns to actually use it. :))The tree is so perfect. We'll hang some fluffy toys from it so that kitty cat can play hunting.
The best would be to train the kitty to learn to use the toilet just like a human ;-) If not we could perhaps install a ventilator and a ventilator shaft to the outside to vent out any odours!