You might think investing just $100 a month is enough to retire comfortably — and in theory, it could be. Find Out: Dave Ramsey Says This is the Best Way to Pay Off Debt Read Next: 4 Housing Markets That Have Plummeted in Value Over the Past 5 Years “If you invest$100 a month from age 25 to age 65 in a decent growth stock mutual fund, it will be $1,176,000,” money expert Dave Ramsey said in a recent YouTube video. “You retire a millionaire.” However, even if you amass a healthy retirement nest egg, one ...