Thanks for all this valuable information. As this is for my first grandchild who will be 7 months old when we will be travelling, this is all new to us, my daughter and son-in-law. He is now in a car seat that is set within a base frame that is anchored into the car. At the time of travelling he will have graduated into a larger car seat that can be seat-belted into place without an anchored base. Based upon the information provided by participants of Better Bidding, the new and larger car seat will be taken on the plane down to Florida rather than renting one from the car rental agency. Again, thanks for this info.