Four parameters do most of the work. The annual limit sets the ceiling, and a limit that comfortably covers an average dog's worst year may not cover a giant's, because the same procedure consumes more drug, more theatre time and larger hardware. The reimbursement percentage decides what share of that bill you still pay. The deductible determines whether small claims are worth making at all. And the waiting period governs when cover actually begins, which is not the day you pay.
The fifth parameter is the one that matters most in this breed: how the policy treats hereditary and congenital conditions. Some insurers cover them, some exclude them, and virtually all of them apply the rule that a condition already showing signs before cover begins is pre-existing and outside the policy forever. In a breed whose two most expensive documented problems are inherited, that clause is the whole product.
Premiums here reflect Omaha's moderate market, but the breed rating does not. Insurers band by breed and size, and giants sit near the top of the band, so expect a quote that looks unrelated to what a friend pays for a terrier.