Islands with city links are amongst the most sought after, with premier city-linked island real estate costing up to four times that on the mainland. Investors looking at property based in islands off the coast of Florida could pay as much as a 90 percent premium on the price of property in its nearest neighboring mainland city.
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Entire private islands are a very small part of the real estate market, which operate quite independently of the wider property world according to the study.
"A private island is the ultimate trophy asset. But financial return is not the primary motivation. These buyers are seeking the ultimate hideaway and a chance to shape their own world. For them, the qualities remote and private are priceless," said Nicholas Candy, CEO, Candy & Candy in the report.
The global UHNW population reached an all-time high of nearly 200,000 in 2013, and is forecast grow by 22 percent by 2018. The growth in wealth will fuel demand for alternative real estate, with a particular boost from Asia, the region where it is set to grow fastest, said Yolande Barnes director of World Research at Savills in the report.
"Second or third generation wealthy individuals, accustomed to money and becoming more interested in its lasting impact, will pay an important role in island markets. We anticipate that a proportion of these philanthropic UNWIs will seek their own "eco domains", islands where they can restore or maintain whole ecosystems and do their bit for the planet," she said.