My cat is 14 years and is...

Question
My cat is 14 years and is on his way out and I can't afford more vet bills when do you call it quits and put to sleep?

Answer
If he has been suffering or is in pain, the most humane thing you can do is put him to sleep.  It is a difficult decision to make but is often the only thing you can do.  Your cat knows you loved him and gave him the best years of his life.  The process is painless and unstressful for the cat.  I know this is hard for you, but pick a pretty spot to bury him and take him to his final visit.  Prolonging his quality of life...or what little there might be is more selfish than what's best for him.  
Kris