You are incorrect in regards the demographic changes taking place in Chicago.  

I incorrectly assumed that since we have $50K in cash and a home that is paid for 100%, valued in excess of 75K, that we would be able to get pre approved for a loan of no more that $30-$40K.

The problem here is that people think they can determine a "return" based on a cap rate that they figure incorrectly.  

I would just caution against not disclosing it is a rental as if it is not written incorrectly, coverage could be denied in the event of a claim.  

You have, in essence, asked "teach me how to perform neurosurgery" and many of your assumptions will be incorrect (thus making you your worst enemy!).

I know my answer, but it may be different for the next guy.I just looked at a house with incorrect sizing to the tune of 600 sf.  

This statement is incorrect.

I know from doing some research that the water numbers that are listed below are incorrect and should be on average $240 a month which leads me to believe that some of the other #'s may be incorrect.

I didn't want to get them incorrect so I just decided I would eat them. 

Oh, and if done incorrectly it will actually hurt your rankings with Google.