I would recommend caution in expecting a car seat rental to be installed (and properly at that) in the car when you get it. I have done this twice with Hertz and have a couple of horror stories to prove it. Also the car seats provided with the rentals are bottom-of-the-barrel. Who knows what temperature and handing extremes they have gone through? I now bring my own. Have your local car seat installers show you the ropes. You'll be happy you did.