Yes
Surely there are chairs everywhere!
Yes, you can rent a wheelchair
They rent chairs for people with reduced mobility
Yes, and it used to be that the valet parking was free for folks who required one. we saw some wheelchairs last night near the valet parking which is by the "Lime" parking garage entrance but I'm not sure if those were pickups or drop offs. The initial garages had Disney Guest Relations locations near where they entered Disney Springs, and it was adjacent to those you could get a wheelchair. But I can't yet be certain about the newer garages toward the East end of the complex. The Lime garage comes out by the big Disney souvenir store although that is not the place you would get them probably. If there is not a way to get them at the East end I would be surprised, and the place to inquire would be right there at valet parking if you don't see a place at that entrance (best place to enter, methinks).
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