The cheapest priced sections should be the Beach and the Caribe. If you stay here, you have access to the entire beach plus all the pools in the Beach, Caribe, Tropical and Colonial sections, together with the beach bars and beach restaurants in those areas. However, you don't have access to any buffets, a la cartes or theatre other than those in the Beach/Caribe sections. You may wish to note that the buffets in the Beach/Caribe are NOT air-conditioned, which may be a big deal depending upon the time of year you plan on visiting.
If you stay at the Tropical or the Colonial, you have access to everywhere EXCEPT the Palace amenities (i.e. pools, beach bars, beach restaurants, a la cartes, lobby bars, buffets and restaurants).
The Tropical/Colonial rooms are slightly larger than the Beach/Caribe ones ... but not by much.
The Tropical/Colonial sections are more central in the entire five resort mega complex.
The Tropical/Colonial buffets are air conditioned.
If you stay at the Palace, you have the run of the total five resort complex.
If you stay at one of the "lesser" resorts, you can upgrade your buffet or a la carte meals by paying an additional charge, subject to availability.
Unless you're looking at visiting the resort during the summer (when an AC buffet is pretty much mandatory), then I don't think it's s worth an extra $750 to stay in the Tropical/Colonial sections.
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