I flew with a dog we adopted on the street in Mexico to US. Volaris was the only airline that allowed me to travel with her. I had to have all the paperwork, including the vaccinations and a letter from her vet. The crate must be a certain size. Try to find a direct flight so that it isn't too long. We flew directly to Ontario, California, in the evening (so it was cooler). Her carte was there when we got off the plane. From there, we rented a car and drove to Portland, OR. Find a way to minimize flight changes. If you must, take a day between flights. Good luck!