If you've ever dreamed of owning your own private island, now might be your chance.

Weak demand and rising inventory for private islands around the world has created a buyer's market, with prices down between 20 percent and 80 percent.

There are now more than 600 private islands for sale around the world, according to Chris Krolow of Private Islands Inc., which helps market and sell islands. Inventory is up by more than a third since before the recession.

You don't even have to be a millionaire anymore to have your own piece of paradise. There are dozens islands around the world priced at $200,000 or less, and a few for under $50,000 (though don't expect a villa and sandy beaches in the Bahamas for that).

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Brokers say that demand remains healthy for high-quality islands - those that have houses, that are close to major population centers, with good beaches. But prices are sinking for the large and growing supply of undeveloped, remote islands that have become the castaways of the high-end real-estate market.

"The recession has divided this market in two," said Farhad Vlaid, of Vladi Private Islands, one of the world's largest private-island brokers, with offices in Germany and Toronto. "The quality islands are strengthening. But what I call 'adventure islands,' that are not inhabited, don't have a hospital nearby and there's maybe a problem with local politics and climate, that market is weakening. The sellers just don't love their islands as much."

Puangiangi Island, a 155-acre rock outcropping off the coast of New Zealand's South Island, was priced at close to $4 million was recently sold for less than $800,000. Buenavista Island in Panama, with more than 200 meters of beaches, was priced at $3 million and is now going for $750,000.

Even bigger bargains include Leaf Cay in the Bahamas. The pristine island has three beaches, deep water docks (perfect for mega-yacht parking) and easy access to a nearby golf course. Leaf Cay was on the market for $24 million, but is now priced at $7 million.

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The Market for Private Islands Is Sinking