I used Dollar last summer, it was my first time renting a car...I was the only adult with my two children and I was a little nervous. I don't remember doing early check in but I definitely did the Dollar Express ahead of time. You have to do this a week or so, at least, ahead of time if I remember correctly because it took a bit of time for it to process. We got our bags and walked out to the garage. We looked at the light up sign, found our name and instead of a car it said see attendant. I was a little bummed at first about that because I really just wanted to get in a car and go but I went to the booth, the employee handed me a packet of paperwork then whispered if you don't see anything in the class you reserved feel free to go to the next class. We were perfectly happy with one in the class we reserved so we loaded up, headed for the exit and were on our way within 5 minutes. Super easy, super painless and I worried a ton for nothing!