Generally you should be able to have an entire vacation with what's all-included at your all-inclusive resort.
But of course, there's an innate human tendancy to spend more, and here are some common ways to do it at an AI:
- excursions such as horseriding, ATV's, explore-the-country
- golf is usually extra (- at Beaches Boscobel, it's included)
- scuba is usually extra (not at Beaches, though)
- snorkeling boat excursions are sometimes included, sometimes not
- spa is always extra
- baby care: probably included, if it's offered; but incurs an extra charge at Club Med
- special outings at the kids or teen club: sometimes the kids program itinerary includes an off-property outing; these will probably cost extra
- at some places, arcade games are an extra cost
- occasionally, use of the fitness center incurs a charge
Check with the individual property, to be sure what's in the deal.
Tipping: most all-inclusives say that tipping is not needed, and at some places it's strictly forbidden. But at other places, dollar bills frequently change hands: read visitor comments at TripAdvisor, and you'll get a sense of whether tipping happens at a particular resort or not.
Elite levels of service: some resorts offer luxuries with higher-priced rooms or suites (such as the Butler service at certain Beaches properties).

