I am on my 3rd Vet with my bullies. The first one always said "I dont know...but he's a bulldog so its gonna happen" Then he charged $100. The second, sounds alot like yours. Even whe he was right about the diagnosis, he wanted to sell me everything he could. Our Vet now, says "lets try.....before we have to do these tests", " Since 2 of your bullies need antibiotics, let me write you a prescription and fill it at Wal-mart.....its free there"
A good Vet will help you figure out the problem instead of just try to charge you an arm and a leg. Unfortunatly, its trial and error. There is a Vet recommendations here on EBN you should it check out. Your Vet should know as much or more about bullies than you do!!