Interesting discussion, but I would advise that it is harder than it looks. As we grow, our lifestyle changes. Getting married and having kids will add significant cost and will likely make you more conservative in your investing too. The S&P500 doesn’t always go up, so some years your investments will reduce. My advice is to find ways to build up cash flow such as through starting a business or by real estate investing. Trying to live on $20k per year, especially once you have a family, is just not much fun at all.