[fintstone]

If not cash and he has deferred gains (like with investment property), there will likely be capital gains taxes. Of course, if invested very conservatively, maybe not much.

If a retirement account like a 401K (that defers taxes), he would pay the rate of earned income. Real estate and similar should be held if possible (to avoid capital gains) ...as it is inherited at current value (step-up). The only capital gains then come if you hold onto the property and it goes up in value (still not a bad thing).

You pay the income taxes annually on the gains in lots of investments like CDs)...so depending on where he has money, he should choose those. Those will have the same gains/taxes as any other year (less if not held the full year). You mentioned Money Market...typically he pays income taxes on the gains of those now....so that would not change. Taxes have already been paid except for current year or current month (depending on how he pays them).