Cat depends how much suffering it will have in the process, it may get worse b4 it gets better in which case may be better to have it put down..i have a cat myself and god forbid if i hate to make the decision...it aint an easy one been there b4 with another animal...

puppy....it shouldnt cost all that much to fix it up

Id sell anything i could to fix any one of my animals...i was prepared to take a loan out for £10k to have my horse treated asked vets if i decided to have her put down would they think it was the right decision they said yes....problem solved....its always worth speakign to your vet BUT they wont tell you what to do, they will tell you if they agree with you decision, but they wont help you make it...