We have a cat that is 13 years old. He likes peeing in the house off and on, usually on blankets or in the dog cage. He does not do this all the time. We do have 4 cats in the house but 5 litter pans ...
I hope your cat gets better, At that age it could be a lot of things and hopefully a good vet will figure it out and tell you what is best for the cat.