Yes, there is an Amtrak ticket counter or a Metrolink automated machine in the courtyard.
Yes, Amtrak and Metrolink
Yes.
You can also buy Amtrak and metrolink trains via their mobile app. I believe you can buy tickets directly from an Amtrak conductor, but I think the only way to buy a metrolink ticket on the train is via the app.
Yes, or on the train
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