I have a cap for anything.. usually it's a $500 cap, becuase that's all I can spare. If I can run a bill, and pay it in payments, I'll go higher, if I feel it's a justified expense. I'm not going to pay $1K for a surgery for a snake that will heal on it's own, given a bit more time and care. I don't spend more on a morph than I do a normal though, becuase to me it's more about the animal is my responsibility, and I will do what I can to have it healthy.
But.. can't get blood from a turnip. If I don't HAVE the money, I don't have the money, period.