Escape to fantasy island.

Shopping for a vacation bargain? For a scant $20 million, you can put down roots in a tropical paradise.

It's the ultimate fantasy: escaping to your own private island, far from phones and fax machines and daily crises. But unlike most fantasies, this one is within reach. In fact, for many board chairmen and chief executives, owning a private island isn't all that unusual. It's almost the next logical acquisition after the penthouse pied a terre in town and the corporate jet.

Back in the early 1980s, Richard Branson, chairman of Virgin Atlantic Airways and Virgin Records, bought Necker Island, a tiny outcropping in the British Virgin Islands. "I had never heard of the B.V.I. before someone told me there was an island for sale down there," Branson recalls. "But since most people assumed I had named my company after them, I decided to have a look around."

The upshot: Branson came, he saw, he bought.

The first question that comes up for island seekers: Where to stake a claim? Most buyers show predictable geographical preferences. The Japanese tend to prefer Polynesia, Hawaii, and anything near New Zealand. The French lean towards islands and the Indian Ocean, while Americans and Europeans favor those surrounded by the turquoise waters of the Caribbean or those near Bermuda. Indeed, these preferences stem partly from geographical proximity. But pursuers of paradise also tend to seek good value. And on that account, as with any real estate, the key is location, location, location.

Because the prevailing fantasies-of-choice seem to be islands of the swaying-palm-and-white-sand variety, the typical Caribbean, Polynesian, or South Pacific islands attract the most buyers. Consequently, these "hot" islands are becoming increasingly scarce as well as increasingly expensive. For instance, the asking price for Guana Island, a singular beauty in the Caribbean, is $20 million. But savvy shoppers can pick up an island off the coast of Scotland for a mere $65,000.

But that's only the ante. Virgin Atlantic's Branson estimates he has spent an additional $20 million on the development of Necker Island, installing his own brand of island civilization. Branson's additions include a sports complex overlooking the tennis courts, dock facilities, a heliport landing pad, and wilderness trails. There's also an infrastructure to pump in fresh water and eliminate sewage.

"Necker Island may be only 74 acres, but it has all the logistical problems of running a small country," Branson says. "These include shipping in raw materials - the daily requirements of life - and supplying energy to provide light and heating. Our main problem is doing all of this without damaging the delicate environment in and around Necker Island as well as the whole Caribbean."

Thanks to Branson's vision, his "small country" has developed into an island paradise so appealing that even finicky Princess Di is on his repeat-guest list. His kingdom is centered around the so-called Great House. Balinese in ambience, the abode is perched atop Devil's Hill, the island's highest point. It is a massive structure of native stone and timber, built pavilion-style, with ceiling and floors, but few walls. The open-air design takes full advantage of ocean vistas.

Why share this paradise with strangers? Branson explains: "I wanted to build a home that could be used by my family and friends for holidays, while keeping the island as unspoiled as possible. However, it seemed a waste to use it so few weeks a year. So, now we rent it out for business meetings, small conferences, or just as a fabulous private holiday island."

To attract such types, Branson commissioned a limited edition brochure, a glossy photographic essay that showcases the more sybaritic aspects of his private paradise. Lavish color portraits are breezily identified by double-entendre captions; to be sure, this is a paradise with a sense of humor. Hence, a rosy-hued shot of one of the decks leading into an open-air bedroom is titled, "Sunset Strip"; side-by-side photos captioned "outdoor pool" and "indoor pool" feature the swimming pool and snooker table.

The layout of Branson's hilltip retreat invites visitors to a near-communal experience, a sort of "houseparty" vacation style for those who enjoy each others' company. For example, everyone sleeps in the same wing of the same house, taking meals together at the baronial table. But guesting together isn't everyone's idea of paradise. Thus, halfway around the world, on two islands in Fiji, solitude seekers see other vacationers only if they choose to.

When Margie and Jay Johnson first bought Kaimbu Island in Fiji, they kept it as their family secret, a haven where they could escape life in the fast lane. That was in 1969, when Margie was a clinical psychologist and the founding director of her own clinic, and just after Jay's sale of Glas Craft Inc., a fiberglass company in Glendale, C.A.

"After I sold the company, I had a lot of money to get rid of," Jay recalls, "So we bought this beautiful island, and we treasured it as our own family retreat for 20 years. Finally, though, we decided to share it - with friends we know and some friends we don't know."

In line with that decision, the Johnsons built three luxurious guest houses in the style of Fijian bures: individual cone-shaped cottages of indigenous hardwoods and bamboo. Appealingly long on native charms, these quarters also incorporate such upscale touches as spacious living and bedrooms, wet bars with stocked refrigerators, and oversized baths with walk-in showers that open onto the beach.

Elsewhere in Fiji, David Gilmour, a Canadian who was formerly a magnate in the lodging, oil and gold-mining industries, holds sway over the island of Wakaya. When Gilmour first bought the island, it was totally uninhabited. But gradually, he completed a home for his own use, eight guest bures, an airstrip, 26 miles of roads, and an entire Fijian village complete with a school and church.

"There was no one living here, so I had to create a native village," recalls Gilmour. "Best of all, I was able to populate this village with 125 Fijians, the most talented craftspeople, artisans, musicians. I provide everything for them--even [educational] scholarships for the children. They, in turn, provide the beautiful environment."

Gilmour's Wakaya Club, which opened in 1990, is a runaway success. "So far, everyone who has stayed here booked a return visit before they left," he reports.

It's not hard to understand why. Wakaya Island, which comprises some 2,200 acres, rolls across soaring cliffs, lush sprawling fields, talcum powder beaches, and virgin forests teeming with wild ponies and deer.

Gilmour's guest bures, like those of the Johnsons, combine indigenous design and amenities, "I think people love creature comforts, especially after a day of beach and sun," Gilmour says. So he has outfitted his bathrooms with six-foot soaking tubs, stand-up showers, three sinks and a bidet. The beds, with their extra-firm mattresses, measure seven feet square. And complimentary sports equipment is state-of-the-art. "I don't want my guests hacking around with junk," says the baron of this manor. So, there's Ping equipment for golfers, and Wilson's Profile-line gear for tennis players.

Indeed, even to the visiting guest, none of these island paradises comes cheap. But the flat that guests pay covers all costs, usually including even the air or water transportation to reach the island from the nearest international airport. Oddly enough, many guests consider the rates a downright bargain, and voice fears that word-of-mouth referrals might spoil their tranquil getaways.

"We put what we thought was a high price on our island--$1,000 a day," said Jay Johnson. "But the word from most of our guests is that we're not charging nearly enough."