My son and his girlfriend are on summer break from college. They've saved their money and have booked a 5 day trip to Cozumel for early August. They are staying at the Occidental Grand. They are on a tight budget now that the air and hotel have been paid. I'm looking for any advice, suggestions for things to do, recommendations for any "must see and do" things on the island and also any warnings or cautions I can pass along to them?
(I've already warned them about the time share BS!)