Cash on Cash Return Only?

[Matt Stevi]

What numbers do you guys use to evaluate deals other than Cash on Cash Return? I'm very new to real estate investing and I've been learning as much as I can over the last month or so, and so I'm just curious to know what other numbers I can run to see if a deal is going to be good or not. 

My #1 goal is to one day grow a portfolio of single family homes + small multi-family homes that cash flow positively, and years from now produce enough monthly income to greatly supplement (and eventually replace) my income from my job (aka, retiring in my 30s).

Thanks!

Matt