Typically, the expenses associated with keeping a service dog are the food and vet bills for the dog. For veterinary questions during the life of the dog, we encourage you to call us for advice. (Mandatory disclaimer: Our health advice, while always available, should not be considered a replacement for veterinary treatment.)
Note that many veterinarians offer discounts on services for assistance dogs.
You can use any brand of dog food you want, but we use and always recommend a no-grain dry food. The brand we use is Orijen at $75 per 28-pound bag (free delivery), which is about twice the price of even the best dog food sold at most stores. Note that online websites like Chewy.com will deliver for free anywhere in the US. You can use any food you like, but we find this high-quality food (either Orijen or a similar no-grain brand) pays for itself in the lack of vet bills,
Tax breaks: Medical expenses in excess of 7.5% of adjusted gross income, including the cost of maintaining a Service Dog, can be deducted from your taxes. Here's the IRS page on medical expenses for more details.