Forbes addresses 7 common estate planning mistakes. To me the highlights are:

1. Not having a plan. This is self explanatory.

2. Using an on-line or DIY service instead of a professional. Estate planning lawyers of years of experience to guide clients and help them make wise choices.

3. Not reviewing beneficiary designations to ensure that they meet current wishes and plans.

4. Leaving assets outright to adult children who might not handle them responsibly or who might not need them.