You can raise rents to match market demand or adjust for inflation to boost your income, but many rental investors choose to use the extra cash flow to pay down the mortgage faster. This leads to super-reliable and higher-than-average dividends -- many of which are raised as the company grows, boosting returns and passive income over time. But there is concern over the continuing recovery for malls, particularly if the U.S. economy enters a recession, which could hurt its already slumping sales and foot traffic further.