Celebrities may have large bank accounts, but sometimes they fail to put adequate estate plans in place, says WealthManagement.com.

Read: Don’t delay planning

Make sure wealthy clients avoid making these mistakes when forming their estate:

Unenforceable last wishes

Diana, the late Princess of Wales, left a letter of wishes directing certain effects be left to her godchildren. The letter was overturned by court because it was unenforceable.

Inefficient bequests

James Gandolfini divided his will into different bequeathals to his wife, sisters and daughter—but doing so cost his family 55% in tax because he didn’t take advantage of surviving spouse incentives.

Verbal promises

Make sure clients have all aspects of the estate in written form. Marlon Brando’s will didn’t include a promise to his housekeeper, and it cost her his San Fernando Valley home.

Protecting against taxes

Since Elvis Presley didn’t have a proper plan in place, 73% of his estate was consumed by taxes.

Read more here.

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