<prompt> Human: Hi folks! Im 26 with no debt, excellent credit, and moderate income -- I save 20-25 of my income now in IRA and a taxable accounts with Schwab no 401k available. My investment portfolio is almost entirely the right one, made of well-diversified cheap index funds. Tools like FutureAdvisor expect an average return of 8.4 from my current portfolio.Is there a prudent way to borrow a bit of money to increase my invested capital? As a super-rational type, if I borrow money at less than 7 or so, I think it should be good for my long-term wealth. I certainly wouldnt get wild and crazy -- I would never borrow more than a few percent of my liquid assets this way.I dont really understand how buying securities on margin works, or if theres a sensible use of Lending Tree, etc., to increase my available capital. Does anyone have any wisdom?  <response>: Does anyone have any wisdom?Your time is better spent increasing your future income prospects than buying securities on margin. The flaw in your reasoning is that while you might get a long-term return of 8, markets can be highly volatile. Your long-term, leveraged investments arent going to matter much when your lender makes a margin call and you dont have enough to cover it. 