How much would you spend to save your dog's life?

My stepdaughter has a beautiful young bulldog named Lily who needs a 3500 dollar operation to have a chance at life. The chances of success are 50/50. She cannot afford it, but feels she must do everything to save this dog’s life. I have my opinion, and have advised her to the best of my ability, but I thought you could also help me and I would pass along your wisdom. Thanks in advance.