I didn't see this thread until I had already written about several other complaints in another thread - but I wanted to add even more comments about the rental wheelchairs here.
I don't need a chair in my daily life, but the walking in the parks is just too much for me. Before going to IOA (Dec. 22), we had spent 4 days at WDW, and I was quite happy with their push wheelchairs. The one we got at the rental desk in the garage at US/IOA had a vinyl mesh seat and back. The seat was much shallower than any other wheelchair I've ever used - and very saggy. The chair was obviously quite old, with no tread on the tires.
By the time we reached guest services, I knew I couldn't cope with that chair all day. Fortunately, we were able to exchange it for another with slightly firmer seat (leather-look vinyl), but the seat was still too shallow. And my dear daughter didn't even mention the fact that the handles were too short and too low - until we visited SeaWorld on Christmas Day, and she raved about how much more comfortable their chairs were to push.
I was also quite offended by the US rental policy. They charged a dollar more than WDW and SeaWorld - AND - they insisted on running a credit or debit card through their imprinter, for a $50! deposit if the chair wasn't returned to the same rental desk. Although they reassured me that they would give me the imprinted slip when I returned the chair, I was still quite anxious. If it somehow "accidentally" got posted, it would have overdrawn my checking account.
Although my daughter and granddaughter and I will probably make another trip together to Orlando in 2 or 3 years, I'll stay at the rental condo if they choose to visit US/IOA. I enjoyed Seuss Landing and Grinchmas, but there were too many inconveniences to get me back there.