Yes. The personnel there will take you down to the train, get a plate for the gap between the platform and the train, then escort you to the appropriate seating. This applies to BOTH Amtrak and MARC trains. BUT, IIRC, it does NOT apply to the light rail streetcars - For the light rail, there is an elevator down to that level and a ramp for boarding the streetcars. HOWEVER, IF there are no Amtrak or MARC trains and Amtrak personnel are available though not part of their assigned duties, i have seen them help to the light rail also.
How wide is base? Penn station Baltimore is (unlike many stations) level with trains. The first row of most cars has space for wheelchair/scooter. And Penn has Red Caps. They will escort/assist you free of charge through doorways, to the elevator, etc. I know wheelchairs can make it, but some mobility devices are wider than others. So the real question is about the width of your base and it's turning radius.
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