The price of $20M (or $90K per acre) is reasonable and actually low compared to world prices for similar quality and proximity to wealthy markets.
They have quality approaching French Polynesian islands, Maldives islands, and Fijian islands, but are in much better proximity to wealthy markets.
Their proximity to the States is not as good as Bahamas, but their quality are much better.
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For World Comparables Click here
For Islands Magazine Feature Click here