Yes, there is a ticket machine in the station. MARC commuter train is cheapest but does not run on weekends to Aberdeen. Amtrak tickets can also be purchased from the machine or your smart phone. If purchasing a ticket on the train there is a $5 service charge, no bills larger than $20 accepted.
Yes, but the conductors are supposed to charge you additional. Your best bet is to purchase from the kiosk in the corner of the station. Just make sure on the first screen to choose MARC tickets, which is usually in the bottom right corner, rather than choosing Baltimore. Then on the next screen you'll choose Baltimore. By choosing Baltimore on the first screen you are purchasing an Amtrak ticket which is much more expensive than MARC.
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