If you're flying, you need to make reservations for your dog, to guarantee that there will be a spot for them, under your seat. The airlines that do allow pets in the cabin only have 2 spots on each flight for pets. I'd never fly a Yorkie as cargo, too many bad things can happen
I always do roadtrips so I don't have to hassle with the airlines. I flew with Starr ONCE and while she did well, they hassled us on our return flight because we were ONE minute late for check in. We had to fly the next day, grrr~!