I would suggest you park in CT or NJ near/at a rail station and commute in.
I dont think I've ever seen a motorhome around there as there is hardly ever parking for a car but I would call parking garages around the area to see if they can accommodate but that too I highly doubt
On the street, you'd have to be really lucky. I would Google the garages inn the area, one of them is bound to be able to accommodate you.
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