 Right now, 65. $200 a month from age 25 to age 65, you'll have between $1 million and $2 million. No, that's not too good to be true. That's based on the long-term average return of the S&P 500. Now, if you're not 25, well, that's okay. You can still get started. A huge predictor of investing success is that you actually invest. So get a pro in your corner to help you get started.