Besides the tax impact you have to deal with, not a topic here, there is little you have to worry about between 收入不错 and 收入错, just like any other investments. Everything comes down to ROI (return-on-investment). "富得cash flow" doesn't bother 投资APT出租? Wrong. Short of time is the real reason (not even the personal preference, interest or perspectives). All people/institution investing in NY, LA, or Chicago downtown are the ones "富得cash flow".
Why picking up time alone? Because time can be used for market trade, just like any other onvestments. In that sense, everybody is pushed by the market, be you rich or poor.