Not sure about the prices, but they have 3 different size lockers. You should be able to keep a small bag in the larger locker. Most people keep their stuff at their tables/lounger/etc, except for any valuables
Yes, you can fit a bag. There are a couple different sized lockers, but most people leave their items by their chairs.
Not sure but I think most people keep their bags with them not sure how big the locker is.
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