It's hard work, but it goes like this (over a couple of months!) only move onto the next step when the cat is comfortable

  1. move the litter box next to the toilet
  2. slowly raise it to toilet height
  3. put it over the toilet seat
  4. make an insert for the toilet with litter in, and small hole for drainage
 (i used a sheet of 5mm pvc iirc, and a heat gun to mould it into a bowl that sat over the rim of the bowl)
  5. slowly use less litter
  6. when there's no litter left, make the hole slightly  bigger
  7. keep repeating making the hole slightly bigger
  8. when the hole is full size, take the insert away

In the end I went back to the litter tray as it was distressing cat 1 too much.

The worst thing about this training is it takes months, and I only had one toilet, and removing the inset litter tray was a huge pita!

There was something quite odd about going to the toilet and it being occupied by a cat though!

Here's a pic of cat3, happy as larry. Even after I put the litter tray back he carried on using the toilet for a few weeks

https://thisaintnews.com/static/user/pics/1219881600/1220319...

I think it would work best if I had 2 toilets, so it wasn't such an effort for me and guests to use it, and if there was only 1 cat instead of 3.

It's too much work trying to train 3 cats to use it at the same time, and to convince them the floor is not a better option

I'd be fearful that if they were toilet trained there'd be some nasty surprises on the seat or the bathroom floor.

I'm sure there's a dark brown side to the glamour of potty trained kitties which we don't see.

I'm going to try teach my cat to fetch using clicker training. When she was a kitten, she used to fetch things I threw and then drop them at my feet.