yooperfan, I believe that you only receive something in writing if you booked on-line. I got my on-line confirmation a day or so later. All you really need is the confirmation number. I have had to change my pick-up times twice in the past and I have never gotten any response from them. But, I have called the 800# and double checked. All was fine. I would suggest calling the day before you leave to make sure they are all set.