Expected Value (EV)

[Agustin Rossi]

I was reading the book "Real Estate by the numbers", the part on EV, and I was wondering on how to calculate the EV when I do not know the probabilities/percentages of each outcome happening, can you give me an example on EV with a rental unit please? I need to know the percentages of the options I have available to choose in order to be able to calculate the EV and choose the best option, the one that will give me the best return. Thanks