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While many of us like to think that we're immortal, the only two things in life that are certain are death and taxes, to paraphrase Ben Franklin. Not only is it important that you have a plan in place in the unlikely event of your death, but you must also implement your plan and make sure others know about it and understand your wishes. Lest, as Franklin also said, "by failing to prepare, you are preparing to fail."

If you've procrastinated on your estate planning, here's a list of tasks to get you going in the right direction:

Must-do No. 1: Inventory physical items.

Go through your home and make a list of all items worth $100 or more. Examples include the home itself, television sets, jewelry, collectibles, vehicles, guns, computers/laptops, lawn mower, power tools and so on.

Must-do No. 2: Inventory non-physical items.

Add up your non-physical assets. These include things you own on paper or other entitlements, including brokerage accounts, 401k plans, IRA assets, bank accounts, life-insurance policies and all other insurance policies such as long-term care, homeowners, auto, disability, health and so on.

Must-do No. 3: Make a list of credit cards and debts.

Make a list of open credit cards and other debts. This should include auto loans, existing mortgages, home equity lines of credit, open credit cards with and without balances and any other debts. A good practice is to get a free credit report once a year and make sure you close out any credit cards that are no longer in use.

Must-do No. 4: List organizations you belong to and charities you support.

If you belong to organizations such as AARP, The American Legion, veterans' associations, AAA auto club, college alumni groups, etc., you should make a list of these. Include any other charitable organizations that you proudly support or make donations to. In some cases, several of these organizations provide accidental-death life insurance benefits (at no cost) for their members and donors, and your beneficiaries may be eligible. It's also a good idea to let your beneficiaries know which charitable organizations are close to your heart.

Must-do No. 5: Send a copy of your lists of assets to your estate administrator.

When your lists are completed, you should date and sign them and make at least three copies of each. The original should be given to your estate administrator (we'll talk about him or her later), the second copy should be given to your spouse or another loved one and placed in a safe deposit box, and the last copy you should keep for yourself in a safe place.

Must-do No. 6: Review IRA, 401k and other retirement accounts.

Accounts and policies in which you list beneficiary designations pass via "contract" to the person or entity listed at your death. It doesn't matter how you list these accounts and policies in your will or trust, because the beneficiary listing will take precedence. Contact a customer-service representative or your plan administrator for a current listing of your beneficiary selection for each account. Reviewthese accounts to make sure the beneficiaries are listed correctly.

Must-do No. 7: Update life insurance and annuities.

Life insurance and annuities will pass by contract as well, so it's important to contact all life-insurance companies with which you maintain policies to ensure that your beneficiaries are listed correctly.

Must-do No. 8: Assign transfer-on-death designations.

Many accounts, such as bank savings, CD accounts and individual brokerage accounts are unnecessarily probated every day. Probate is a costly and avoidable court process in which assets are distributed according to court instruction. Many of the accounts listed above can be set up with a transfer-on-death feature to avoid the probate process. Contact your custodian or bank to set this up on your accounts.

Must-do No. 9: Select a responsible estate administrator.

Your estate administrator will be responsible for following the rules of your will in the event of your death. It is important that you select an individual who is responsible and in a good mental state to make decisions. Don't immediately assume that your spouse is the best choice. Think about all qualified individuals and how emotions related to your death will affect this person's decision-making ability.

Must-do No. 10: Create a will.

Everyone over the age of 18 should have a will. It is the rule book for distributing your assets, and it could prevent havoc among your heirs. Wills are fairly inexpensive documents to draft. Most attorneys can help you with one for less than $1,000. If that's too rich for your blood, there are several good will-making software packages available online. Just make sure that you always sign and date your will, have two witnesses sign it and obtain a notarization on the final draft.

Must-do No. 11: Review and update your documents.

You should review your will for updates at least once every two years and after any major life-changing events (such as marriage, divorce or birth of child). Life is constantly changing, and your inventory list is likely to change from year to year, too.

Must-do No. 12: Send copies of your will to your estate administrator.

Once your will is finalized, signed, witnessed and notarized, you'll want to make sure that your estate administrator gets a copy. You should also keep a copy in a safe-deposit box and another in a safe place at home.

Must-do No. 13: Visit a financial planner or estate attorney.

While you may think that you've covered all avenues, it's always a good idea to have a full investment and insurance plan done at least once every five years. If you're not looking to spend the money for professional help, there are several good books out there on getting your financial plan and estate in check. As you get older, life throws new curveballs at you, such as considerations for long-term care insurance and protecting your estate from a large tax bill or lengthy court processes. Tips like having an emergency medical contact card in your purse or wallet are little things that many people never think of.

Must-do No. 14: Initiate important estate-plan documents.

Procrastination is the biggest enemy of estate planning. While none of us likes to think about dying, the fact of the matter is that improper or no planning can lead to family disputes, assets going into the wrong hands, long court litigations and huge amounts of dollars in federal tax. At minimum, you should create a will, power of attorney, health care surrogate, trusts and living will, and assign guardianship for your kids and pets. Also make sure that all concerned individuals have copies of these documents.

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Must-do No. 15: Simplify your life.

If you've changed jobs over the years, it's likely you have several 401k-type retirement plans still open with past employers or maybe even several different IRA accounts. While this normally won't create a big problem while you're alive (except lots of additional paperwork and account management), you may want to consider consolidating these accounts into one individual IRA account to take advantage of better investment choices, lower costs, a larger selection of investments, more control and less paperwork/easier management when assets are consolidated.

Must-do No. 16: Take advantage of college funding accounts.

The 529 plan is a unique tax-advantaged investment account for college savings. In addition, most universities do not consider 529 plans in the financial aid/scholarship calculation if a grandparent is listed as the custodian. The really nice feature is that growth and withdrawals from the account (if used for "qualified" education expenses) are tax-free.

Now you have the ammunition to get a pretty good jump-start on reviewing your overall financial and estate picture; the rest is up to you. While you're sitting around the house watching your favorite sports team or television show, pull out a tablet or laptop and start making your lists. You'll be surprised how much "stuff" you've accumulated over the years. You'll also find that your inventory and debts lists will come in handy for other things, such as homeowners insurance and getting a firm grip on your expenses.