Diversify safely but DIVERSITY. You do not need to get the best and highest return all the time. If so, you are not earning passive income you are earning active income which is taxed differently (see IRS.GOV passive -vs- active income definitions). As an investor you do not need to be chasing ‘the almighty dollar’. This is a losing proposition. Make the dollar come to you.

Passive residual income is generated as a result of little or no direct involvement in the actual creation or production of the money. In essence, passive residual income is income that you may have stirred up, but it is still coming in whether you work or not. With income such as this, you are your own boss, or buying of stocks that pays dividends. You set your own hours and the hours that you do put in are not directly involved in the amount of revenue that you create.
People have a lot of stuff—and they’re always looking for inexpensive ways to store it. What could be easier than having people pay you to store their stuff? Building passive income by offering storage could involve a large-scale investment of buying a storage facility (with cash!) or something simpler like offering your basement or shed. You’ll just need to ensure their items are safe and secure.
​If you pay your bills with a credit card make sure it offers cash back rewards. You can let your rewards accrue for a while and possibly put the easy money you earned toward another passive income venture! (Be sure that the card you select doesn’t have an annual fee or you might be cancelling out your rewards). Check out this list of the best Cashback Rewards Cards.
Well written piece, but I question the core premise. Why the fascination with maximizing “income” (passive or otherwise). Shouldn’t the goal simply be to maximize long-term after tax growth of your entire portfolio? If this takes the form of dividend paying stocks, so be it. But what if small caps are poised to outperform? What if you want to take Buffet’s or Bogle’s advice and just buy a broad market index like the S&P 500, (no matter what the dividend because you’ll just have it automatically reinvested to avoid the transaction fees).

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