I agree with the other posters. Definitely do your research. We had to do a lot of research prior to breeding the sugar gliders and other exotics we have; associated laws (not just federal but local ordinances), costs, diet, etc.
It's more a passion for the animals than for the profit. Trust me. We spend a lot on food, supplies, care, supplements; they live like royalty and eat healthier than we do. As matter of fact, oddly enough, we eat better now (more fruits and vegetables).
You have to find a veterinarian that will see exotic pets and will sign off on sponsorship for the USDA form. The veterinarian will also conduct their own inspection (ours did at least wanted to do a pre-inspection before signing off on the form). They will conduct the visit a minimum of once a year or however the vet and you decide to work out an inspection schedule (more along the lines of what the vet will say). Also, find more than one vet. Always have list available of vets in the event anything should ever happen (the vet quits, stops doing USDA sponsorship, not available for emergencies, etc). Up where I'm at in Virginia, there's not a long list a veterinarians who would do this for the simple fact that either don't have the time, or, don't even know what you're asking about.
Also keep in touch with the APHIS office to ensure after you've submitted your paperwork that they have confirmed receipt of your application.