I haven't come to that yet, but when our 3 year old GSD went blind, even though it was an elective surgery it wasn't a super difficult choice to spend that much to restore his sight (cataract surgery) given that the same problem basically can't come back. He is six now, and it has really improved his quality of life (he enjoys chasing sticks in the lake again). If he was 10, we would probably not have made the same choice to spend the money; because he would get much less benefit from it.

You spend more time with your dog than most people, and I certainly care about him more than any person who is not in my immediate family.