Question: We are a retired couple with three grandchildren, all under six. We would like to leave $20,000 to each grandchild in our wills -- but would like to know at what age it would be best for them to get it .

If they get the money at 18 when they are ready for college, they may blow it and not go to college at all. Maybe at 25 they would still be too young. What is your opinion of age 30, when they are likely to be thinking of buying a home ?

Answer: My opinion is that it is unwise to try to control your grandchildren's lives from the grave. You can't possibly forsee what the circumstances will be 20 years from now.

For instance, by the time a grandchild is 30, he or she may be sufficiently advanced in his or her career that the bequest loses much of the value it might have had at an earlier age.

However, I agree that at 18 they may not be ready to handle, a large sum of money. Fortunately, there is a fairly simple solution.

In your wills you can establish a testamentary trust for each grandchild. You can direct the trustee to dispense income and principal only for the payment of tutition and other expenses related to attendance at college.

But I suggest all funds remaining in each trust be transferred to the beneficiary grandchild either upon graduation from college or at age 22, whichever comes first.

There is no guarantee, of course, that one (or all) of them won't blow the legacy at 22. But at least you will know that the money has been used, as you wish, for college expenses or, if the grandchild does not go to college, the money will come when he or she is an adult and presumably more mature.

I add ny usual warning: A trust is a complicated legal document. Be sure you get expert advice from an attorney experienced in wills and trusts, if you decide to go this route.

Q: I am writing regarding your statement (Sept.8) that a person "can add tolls and parking fees" to intemized deductions on the federal tax return. I drive to work and pay $61.60 a month in parking fees. Can I deduct this amount on my tax return ?

A: No. Commuting expenses to and from work is not an authoriized tax deduction.

In the column you cite the reference to the deductibility of tolls and parking fees only related to those circumstances in which the basic car expenses were deductible.

This might be, for instance, the case of an outside salesman calling on customers, travel expenses between two places of work on the same day or travel to a meeting in another city.

When the transporation cost itself is deductible, then you can claim tolls and parking fees in addition to the standard mileage rate (20 cents a mile this year) or the computed expenses of operating your car.

But when the transportation expense is not a valid deduction, tolls and parking fees are not deductible either.

Q: My house is valued at $125,000 and is paid for. In your opinion is it financially sound for me to refinance this house now and invest the proceeds in tax-free municipal bonds? Since I'm in the 43 percent tax bracket, a substantial portion of the mortgage interest would be deductible on my tax return, so I would have considerable net disposable income.

A: It won't work. You may not claim a deduction on your tax return for interest paid on money borrowed to buy tax-exempt securities.

So the numbers don't add up in your favor. If you have to pay 13 percent on the mortgage, then recoupe, say 9 percent on the municipal bonds, you lose money on the transaction.

Obviously this kind of exchange only pay off if the money you borrow costs less than the return you can get. This is what makes a policy loan (against the cash value of a whole-life insurance policy) attractive.

In this case if you borrow at a cost of 5 or 6 percent, then generate 9 percent tax-free income with the funds, you come out ahead even through you can't take a deduction for the loan interest.