The cost of buying a Caribbean island can vary greatly depending on the size, location, and amenities of the island. For example, a small, undeveloped island can cost around $200,000, while a larger, more developed island with amenities can cost millions of dollars. In some cases, the cost can exceed $10 million.

Can you buy a private island? Yes. In most cases, you will need a deposit of 10 percent of the purchase price to enter into an agreement of sale. You will also need to arrange for a jumbo mortgage or private financing to cover the remainder of the purchase amount.

Virtually all islands in the world are claimed and governed by some national government. That nation's laws apply, and any attempt by the owner to claim sovereignty would generally be unrealistic.

There are tens of thousands of private islands in the world, ranging from a few dozen square feet to hundreds of square miles. Usually, they are governed by the laws of a nearby country but restricted to use by the owner alone.