The Trickiest Items to Pass On to Your Heirs

So you've finally made an estate plan. Your kids get a nice inheritance, your nephew gets the baseball cards, and your cousin gets Grandma's ring. But with some assets, it's not that easy to impose your will. Here are a few that can cause surprise headaches—and how to handle them.

Vacation Homes

Sharing is hard. Conflicts can arise when one sibling lives farther away, earns less, or wants to sell his share, says Tracy Craig, an estate-planning attorney in Worcester, Mass. "One of the worst things to do is to leave property outright in equal shares," she says. "Anytime you have more than one person who owns real estate, you have a potential problem."

The fix: Talk to your kids first to learn their preferences, then put the real estate in a trust and make your heirs the beneficiaries, Craig says. The trust structure lets you spell out under what conditions the house can be sold, how a sharing schedule will be decided, and who pays for upkeep. If possible, reduce conflict by leaving extra money to cover costs.

Pets

Until recently, provisions that left money to pets were often unenforceable, says Gerry Beyer, a law professor at Texas Tech University. If you gave your friend Jack $10,000 to take care of your dog, what was to stop Jack from taking your money and abandoning Lassie?

The fix: Every state except Minnesota has now passed a "pet trust" law, which means if you add a simple line to your will explaining who takes the pet and how much money is provided for its care, probate court will appoint someone to enforce the provision, Beyer says. Want absolute control? Draft a detailed pet trust. (Your estate attorney may not even charge extra.) Name the caretaker and the trustee, set aside money for food and vet bills, and leave care instructions. Care instructions can include to have a pet insurance policy - Money's Best Pet Insurance Companies can provide you some options. Technically, the trust will own your pet, so if the caretaker doesn't meet your standards, the trustee can assign care elsewhere.

Airline Miles

Frequent-flier miles can be worth a tidy sum, but you might not be able to pass on the wealth. Some carriers explicitly say you cannot bequeath miles. And policies change; Delta disallowed mileage bequests in 2013.

The fix: First, ask your airline. You might be better off spending down miles now, Beyer says, buying trips for other people if you're traveling less. (Avoid transferring miles, as you can quickly rack up fees.) But even carriers that officially bar fliers from bequeathing miles—like American Airlines—often allow it on a case-by-case basis, so do name a conditional beneficiary in your will. Heirs may need to request and complete an affidavit and provide the death certificate.

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