At 7% growth, investing SS collected from 62 until 70 will result in a sum equivalent to 130 months of payouts at the age 62 level. This means that the delay until 70 will never generate as much value as drawing at 62 and investing will. At a mere 2% annual growth on investment, delaying SS until 70 doesn't match the value of drawing and investing at 62 until you are over 100 years old.

Since this would be "play" money, it stands to reason that it could easily be invested with a relatively higher rate of return. Online calculations only show that a later draw results in more money because they assume you are a poor bastard who spends every penny to survive in retirement instead of investing.

If the goal is to treat the portfolio value like a high score, draw at 62. If it's to spend money in a more meaningful way than the Federal Government will, draw at 62. The only good reason to draw at 70 is that you are broke and can't afford to stop working until you can draw that much money to support your lifestyle.