What is the simplest mistake you can make to cause major harm to your intended estate plan - and to the people you wish to provide for through that plan? It is having outdated (or missing entirely) beneficiary designation forms for your IRAs, employer-provided retirement savings plans, life insurance policies and other valuable financial accounts.

A few weeks ago, I discussed the seemingly unintended impact the Tax Cut and Jobs Act (TCJA) had on the repayment of overpayments from employer plans. In essence, by eliminating the deduction of itemized miscellaneous expenses subject to 2% of adjusted gross income, the new law negatively impacted some repayments to employer plans - namely, repayments that are $3,000 or less. Similarly, by amending the tax code section on casualty losses, Congress has limited the ability of some plan participants to qualify for a casualty loss hardship distribution.

You may be interested in contributing to a Roth IRA but think your income is too high. You are probably aware that there are income limits that apply to Roth IRA contributions. For 2018, if you are married, your ability to make Roth IRA contributions phases out when your Modified Adjusted Gross Income (MAGI) is between $189,000 - $199,000 and between $120,000 - $ 135,000 if you are single. Are you out of luck if you are a high earner? The answer is "no" and tax reform makes this clearer than ever.

The U.S. Tax Code is a 74,000-page document with interrelating laws and regulations. Therefore, any time Congress enacts a piece of legislation as massive as the Tax Cuts and Jobs Act (TCJA), there are going to be unintended consequences, or as I like to call it, collateral damage. After passage, it's up to the IRS to sift through the damage and clarify any unresolved issues.

This week's Slott Report Mailbag answers readers' questions about profit sharing plans and RMDS and SIMPLE IRAs.