My mom made a ""reservation"" with this service (Tucson Phoenix shuttle). She was suppose to leave early the next morning and they called late at night to say she'd have to pay $70 to take the shuttle because there were not enough passengers for the trip. Luckily she was still able to make reservations with Arizona Shuttle, who informed me that they have no such ridiculous policy.
Cons: unreliable, will cost you more in the end
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