My Grey has traveled with me to out of state trip thrice, overnite at my mom in law's house. The only problem was she wouldn't want to eat if caged. She wanted to be out of cage and liked to play on the window grille. Being at a new place, she was quiet and would not fly. If going to a place where I need to put up a nite and the house was not convenient to have all the windows and doors shut, I would not go. My wife would go without me and the fids. When I went to my parents' house, I would have my Grey harnessed in the house. My Grey would stay with me all the time.
My grey travels a lot in the car. I won't cage her on short distance trip (1 or 2km). She likes to perch on the head rest. She has no problem wearing the harness in the car. Usually I put her on the steering wheel to put the harness on. She won't fly out of the car when the door is open.