By the time you reach retirement age, you may have accumulated a 401(k), IRA and other investment accounts, along with insurance policies and physical properties. You’ll use some of these assets to support your retirement, but the rest may end up in your estate — which is why an estate plan is so important.So, to leave a legacy for your family and those philanthropic groups you support, you need a comprehensive estate plan — and you need to avoid making mistakes. Here are some of the most common ones:Procrastinating. Estate planning, and its implications about our mortality, may not be ...