I dont know what to do since mine was a kitten he has peed on furniture .So i cover my arm chair at night and a got a sofa you could wipe down.
I have had to kick him out my daughters room as he peed on her sofa
and although he seemed ok with the sofa for a while he has started peeing on it
he has now peed on play clothes in a toy box
he is so very loved and has multiple litter boxes across the house
i don't know what's causing it at the vet he's healthy ,it just seems like a behaviour he has had since kittenhood
all i can do is lock him in the kitchen/downstairs bathroom at night. As he only pees on stuff at night .I feel terrible for doing this though but its the only thing that stops him peeing