Online ROI Calculators and or formulas

[Anthony LaGuardia]

Hello, 1. I am just starting to expand on my portfolio of income properties. Does anyone have links to (free) great ROI formulas, excel spreadsheets, or calculation sites? 2. Also. If I'm financing through a bank. What is a good and great % return on my money? 3.Lastly, what are some big red flags (ones other than the obvious like water Dana he) I should keep an eye out for as I tour each prospective property. Thank you for the help in advance! Anthony LaGuardia