The second person didn’t start until she reached age 35. Then, realizing that she needed to catch up, she kept investing $6,500 a year for the next 30 years. That amounted to a total of $195,000 in contributions. At age 65, her account was worth $544,710.90.Again, that’s a nice nest egg. But consider this: She invested much more money than the early bird, made regular contributions for a much longer period, yet still lagged her counterpart by more than $14,000.When Money Is ScarceClearly, starting early is better, but sometimes, and especially in your 20s, you may just not have the money.In that case, Ms. Bruno suggested considering a Roth I.R.A. as a kind of do …