I certainly see the enormous advantages those with tons of equity have.

Biggerpockets is full of great information including enormous amounts of info on property management!

You can find an enormous amount of free information on youtube. 

Question 2, (and 3 and 4) would require an enormous amt of question and answer.  

We've seen enormous amounts of large scale development in terms of housing and general commercial to support the influx of new city inhabitants. 

@Stephen DeFalco Chicago is an enormous market, and I think you should start with the end in mind here.

We have an enormous amount of equity ($600k+) in our primary home, and we currently have a 15yr  mortgage with an interest rate of 1.99%. 

I love TK providers that find the ugly duckling in a good or up-and-coming neighborhood, renovate it at a good quality (without going overboard) so it appraises at or slightly above the asking price, and then has a property management team in place (in-house) to manage the property.It's not always possible to find such an ideal solution, so the relationships of the different parts of the deal (finding, renovating, managing) are very important and a track record makes an enormous difference.

The differences in cost can be enormous.

Any "on market" properties will have an enormous amount of competition and that will drive the price up.