You can purchase tickets right before the bus ride down at the customer service desk and it's best to arrive at least 30 mins before the bus departure time to ensure your seat being a first come first serve basis so it's better to buy the tickets online at the Concord Busline Website.
If you are going to a station ... Like In Agusta ....you can purchase your ticket there at time of boarding But if you are going to an area that is just a bus stop I believe you must have a ticket with you
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