yes, actually NPV, IRR the same thing in your list 1 and 2

I followed almost the same strategy as yours. When I have to decide whether to invest, no matter for equities or real estate, I set the following rules to follow

1) profitability: no matter calculated from cap rate, ROI, or irr, it has to be above 7%

2) liquidity: liquid ratio has to be at least 105% for every single assets, and 145% overall for my whole business. Working capital ratio has to be 200%+

3) solvency: it has to be at least 100%, gearing at 30% to avoid the risk of unexpected rate change