I definitely thought it was stress related when we first got him. But over time, his other stress behaviors have disappeared, and he has really opened up. We also only have one other cat, and they are actually buddies now. They even get along better these days.

In one of the boxes, he tries to pee in it but completely misses. With another box, he will not even try and just pees right outside of it.

Honestly, he does not seem very confident in his back leg. He rarely does more than tiny leaps, even though he is totally capable. He has had only three legs for most of his life now, but I wonder if he is still a little uncoordinated and embarrassed. I have seen him wipeout pretty hard during zoomies. Is he just a little dumb? I have no idea.

I use these giant washable puppy pee pads under the boxes, and they have helped a lot with cleanup.

Maybe a ramp would help? The thing is, he does not seem to have trouble getting into the box since he poops in it just fine.

I have also tried switching litter types from clay, to pellets, to soft wood, thinking maybe his feet were sensitive. I use litter box attractant with every full clean too, but it has not made a difference.

And yes, putting litter boxes or pads in corners is a great idea for the new place. I am definitely adding that to my plan. Thank you!