It can be a challenge to find a veterinarian that specialized in certain species and breeds of pets. This is simply a supply-and-demand situation that naturally increases costs. Sometimes exams, tests, operations, etc. are much more difficult with exotics because of size (think about treating a gecko, gerbil or other tiny pet!) or special needs/sensitivities. The more difficult a pet is to treat, the more expensive the visit is likely to be.