Yes I saw them while I was there. But I don't know where to rent one
Yes they have them for rental around the park. Get there early.
Yes, I would suggest booking it in advance just to make sure that you can secure one
Yes, I will attach the link to this message. They rent out day lockers if interested. https://site.universalorlando.com/minisite/Theme_Park_Hours/wheelchair-stroller-rental.aspx
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