Yes. You buy the cards from the attendants then charge them in the machines.
Yes, you can buy it on any station.
You actually do not need to buy the cards, they are free. Alewife is one of only a handful of stations that have them. THEN you do go out money on them, but the card itself is free
Yes you can
Yeah
Yes you can, not sure about the hard plastic ones, but definitely can get paper. You can probably request one from information, but I believe the cost $5.
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