I ran some numbers for improvements the home would need to be necessary for future renters (current tenant elderly and moving soon).

I wouldn't have any trouble finding a new renter in the Chicago winter. 

I recommend looking at comparable properties to see what the unit is worth if you were to look for a new renter.

Set expectations for renters.

I don't have any properties in the area but I'm one of the millennial techie types in the area who also is a renter.

With the right management, especially a company that's dialed into the European and Canadian renters, quality homes will rent, and not just in the winter months. 

There are also talks about Centene corporation west coast headquarters coming there soon that might bring in a lot of employment and hence, renters. - Any thoughts on if this would be a good place to start off with? 

If he's a bad renter, you'll find evidence of that during your application process, he won't qualify, and you won't have to rent to him. 

According to the Holton-Wise Property Group FAQ, they don't charge tenants for water due to the city's policy (specifically referring to this thread: https://www.biggerpockets.com/forums/731/topics/741251-how-to-handle-water-bill).I've seen others say they either bill-back the tenants for water or have a clause in their lease which states that renters pay anything above $X and that an eviction can occur for nonpayment.My question is as follows: in both of the above scenarios, the property owner is always accountable for the bill. 

If the units are somewhat nice and in a decent area you shouldn't have too much of an issue finding renters.