Don't give up!
Age and kidneys
Cats without a home
Old cats, as old humans, have problems with their joints and as with humans it can help if they eat glucosamine. There are several alternatives for cats but many times it also includes vitamines and other nutritions.
One needs to be careful when it concerns a cat who has kidney problems in that it is best to give the cat as pure glucosamine as possible, since the other ingredients can strain the kidneys. I can recommend Cosequin. It can be bought on the Internet and is manufactured by Vet Nutra.