Trust me I understand dogs and allergies. I have a golden retriever that I have to take to our local veterinary college. He has a dermatologist. I spend $90 per month on his allergy medicine. So far so good as far as this allergy season goes. He's my baby and I will do whatever it takes to make him less miserable.
I also understand bladder stones. My mutt girl had those; complete with the emergency surgery. I have found that cranberry capsules work wonders as a preventive (YMMV). She gets 2 capsules with each meal.
Dogs are worth it though.