About Richard crenian. Perspective landlords buy rental properties to obtain a better return on the investable funds than additional options like the stock market and bank interest rates. Although formulas exist for calculating "Net, Net" returns for commercial property, they are not what investors use initially to examine rental properties.…About Richard crenian. Perspective landlords buy rental properties to obtain a better return on the investable funds than additional options like the stock market and bank interest rates. Although formulas exist for calculating "Net, Net" returns for commercial property, they are not what investors use initially to examine rental properties.WWWW…