Nick Faldo hopes his will be deemed fit for playing golf, John Lennon allowed hippies free rein over his, Mick Jagger and the late Princess Margaret enjoyed the same one, the most expensive example in the world has a highly unusual shape and Marlon Brando encouraged Johnny Depp to get one just like his.

As private property goes, nothing beats a private island for exclusivity, privacy and status symbolism. So of the thousands of privately owned havens worldwide, it’s little wonder that a disproportionate amount are owned by celebs. A vast expanse of water is the best possible way to paparazzi-proof a property, keeping insistent fans and noisy neighbours literally at bay.

Few “normal” people would even consider island ownership without the yacht, fame and bank balance that seem to go hand in hand with it. But, at any given time, a few pretty, habitable and affordable islands are for sale on the open market in Ireland: right now one is for as little as €75,000.

The isle in question is Big Yellow Island, which is neither big nor yellow, but just three acres in size and covered with trees. Located in Hudson Bay near Athlone, its selling agent, HOK, has pitched it at roughly the same price as a ruined cottage anywhere in the countryside, though Big Yellow is just 0.4km away from civilisation.

The most expensive sea sanctuary on offer here costs €5m: 79-acre Illanteige island near Castlebar, Co Mayo, being pitched to islomaniacs through Helen Cassidy’s Premier Properties Ireland. Cassidy has sold several islands off the west coast and is also marketing Rosbarnagh in Clew Bay for €350,000.

Other islands sporting for sale signs around the country include Horse Island and Carbery Island off Co Cork and Island Mor in Clew Bay. But no single island, Irish or otherwise, is likely to make as big a splash as Vatu Vara.

One of only six fully titled, habitable islands left in the Fijian archipelago, it is currently owned by an American artist who stands to make a packet. Vatu Vara — also known as Hat Island for its shape — is 3km wide, with mobile phone reception and satellite systems for internet and cable. It is seaplane- and helicopter-ready and has miles of white sandy beaches lined with coconut palms and a series of clear blue lagoons packed with fish. Yet only the most liquid of celebrity buyers could afford to take a fancy to Vatu Vara. It’s on the open market with the largest price tag of any island in history: $75m (€60m).

Whoever Vatu Vara’s Crusoe turns out to be, they’ll likely have made a good investment. The price of rare freehold land in Fiji is soaring. Elsewhere, island owners are also sitting pretty. In parts of the Caribbean, for example, the price of islands has increased by almost 300% over the past 10 years. An island’s value, as a rule, tends to grow. Or, at the very least, stay afloat.

“Islands are trophies, and their premium passes from owner to owner,” says Cassidy.

Prices, she says, are also demand-driven. “There are always a handful of islands for sale in Ireland, but the pool of buyers tends to be quite shallow. As trophy properties, people who view them are looking for isolation, tranquillity and something to boast about. Even if the island has only cost them €150,000, it’s a very proud thing to be able to say you own one.”

Cassidy shows the islands on her books by hired helicopter. “That’s the only way to see an island, from the air. On occasions I’ve got into a rowing boat in my high heels and my suit, and I’ve even been known to row them there myself,” she says.

From the late 1990s until very recently, most of Cassidy’s viewers were foreign. Nowadays, most are Irish. And despite the “bling” image of the private island, not all are millionaires.

Duvillaun Mor recently sold for in excess of €1m, but its little sister island, Duvillaun Beag, fetched just under €250,000, roughly the cost of a half-acre site in a good area. Islands in lakes tend to be smaller and less expensive than those offshore.

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