You have to rent a Cabana and enjoy the private cove. This is where they get you. If you don't you go to the super overcrowded beach where its tons and tons of people and the water isn't nearly as nice. Everything costs.
Cozumel is great if you're a diver and have diving booked. Otherwise, its not super impressive. You are much better off going to Playa Del Carmen on the Ferry but that ride kinda stinks.
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