The cat has kidney failure and in my opinion, he suffers from it for at least 6 months if not longer. Don't say inside they cannot get ill. This one loved to eat plastic and plants aren't safe either. It started in Spring so can be (it's a tomcat) he didn't like to stay inside (well, he was outside as well but protected in a cat ren/cage so he's safe for the wolves although he escaped several times through the window.).
He had an infusion yesterday and this morning (better not to ask about the prices charged for not doing too much it was 100 ml) and that was it. The last time he ate was 6 days ago so he has a "fat liver" and the idea is that he will eat (he refuses and the expensive, special food makes him gag like all the other things we let him sniff at. This afternoon we tried the syringe (my son wrapped him in a towel because he is strong enough to fight back). If he had 2 ml it was much LOL.
I try later but I will go to bed.
The only positive thing is that he pees and get's out of his bed because he hates it and my son can do the laundry.

I don't think he is a very strong cat. I remember the lady he came from, all incest and the kittens weren't in a very good condition. It took very long before he grew and became a bit bigger (1.5 years old or so) but he behaves like a dog and plays hide and seek which is very cute. It's my son's friend so it will be a problem if he dies but at least they can spend a bit more time together.

You are lucky to have a vet still willing to pay a house visit. We had an old one doing it but he's gone. More a vet as in cows instead of pets.

The other vet killed pups of mine and I don't have much confidence in his knowledge. I rather hear "I don't know" instead of trying whatever pops up in his mind to cash out. One pup he should "save" died after a shot f him on the way back home. I decided to save the other pup myself, since I have enough knowledge although no longer the meds and most equipment since I stopped with the shelter a few years ago. That pup is still alive and a happy, healthy wolf.

The good news is there's a new vet in a village nearby. My son went over there and at least she gave him a better feelings which is important as well.

Thanks for asking. I hope your cat is doing well and it will remain this way. We have periods where cat haters throw poisoned food and many cats become the victim.