Incorrect pick up information.
Address provided for the pick up point was under construction and fenced off. There was absolutely nothing to indicate where the pick up point was. I waited for 20 minutes, finally calling their lousy customer service agent who could STILL not tell me where the van would be leaving from. All she could do was make excuses that they were told construction was supposed to have been completed (and in the end, the customer is supposed to be responsible for that). After talking to her, I eventually saw the van leaving (as I ran up behind it waving and whistling) - not from the pick up address, but the alley next door and somewhat behind the building...totally unmarked. The customer service agent insisted that shuttle could not wait one minute (which would have worked), and then the next van didn't arrive until it was already 7 minutes past its pick up time.
Lousy information, lousy communication, lousy customer service. I did think the van driver was quite professional, but I would never, ever do business with Arizona Shuttle again.