My husband is 82 and he had zero issues. I've had both knees replaced and I thought it was an easy ride. It depends on the person. If you're in relatively good shape, you shouldn't have any problems.
I would say it depends on whether you're in a 2 or 4 seater. In a 4seater with 2 other younger adults it would likely be cake. With only one other adult, while I have not been in one myself, I would expect it to be more on the challenging side of the scale.
I think it would depend on the person, but if they're going with three others, it's possible they can just ride along while the other three do the labor.
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