QUESTION: I pay 0 a month for private mortgage insurance. Should I borrow from my 401(k) to pay down the principal and use the 0 toward repayment? Is there more value in this strategy than having it evaporate into the insurance?

– David Cantu, Corpus Christi, Texas

Nothing worse than evaporating money, we say. But financial planners are rarely fans of raiding a 401(k), since borrowing from your nest egg can have hidden costs. Be sure, says Danelle Kronmiller, assistant director with Des Moines, Iowa–based Principal Financial Group, to factor in the loan’s interest rate and related fees—not to mention any missed investment returns. If you took a five-year, ,000 loan in 2005, for example, and had been invested in an index fund based on the S&P 500, you would have forfeited about ,500 of growth.

QUESTION: Our children have graduated from college and are 25 and 30. Is there any way we can be released as a cosigner from their student loans?

– Todd Staples, Morris, Minn.

It depends on the type of loan. Federal loans like the PLUS and Stafford usually don’t require cosigners in the first place. Many private loans, such as those from banks or credit unions, do have a cosigner release option, which can typically be invoked after a period of on-time payments. For loans from Sallie Mae, one of the nation’s biggest sources of higher-education funding, that period is 12 to 24 months, says a company spokesperson. Have your kids check with their lenders.

QUESTION: I am over 74 and still working. I understand that I have until Apr. 1 of the year after I retire to take my first required minimum distribution from my 401(k). How is the amount on the first distribution calculated? I’d like to let the 401(k) grow as long as possible.

– Donald M. Pries, Oak Lawn, Ill.

The math is actually pretty simple, and you don’t have to do it yourself. To determine each year’s withdrawal for your 401(k), the company that runs your plan takes the account balance of Dec. 31 of the prior year and divides it by your life expectancy, estimated using a “uniform lifetime” table from the Internal Revenue Service. But remember, says Jesse Wilson, a certified financial planner with El Segundo, Calif.–based Financial Finesse, that first year you’ll actually be pulling out two required minimum distributions—and coughing up taxes on both. Your pre–Apr. 1 withdrawal covers the year you retired; the current year’s required minimum distribution must be taken by Dec. 31.

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