Are you renting a car? If so they will allow you to rent two from them. If you are using a taxi/shuttle service, a seat belt will do until you reach hotel. I have family there in SJ and travel there often, we have brought our own from home for the flight but found it was easier to rent one with the car or buy a used one from consignment shop and then when your through just sell it back to them. And since the carseats are so cheap now a days, I once bought one on sale in Kmart since the car rental place claimed they had no more for us and at the end of our vacation just left it behind!