Go to Etsy and search for "rental property tracker," and you will find hundreds of nice spreadsheets to track 10-20 rentals, usually for under $10.Software has extremely helpful features like online payments, marketing syndication (click a button, and your property is advertised on multiple sites), electronic document review/signing, maintenance tracking, and owner reports.

I recommend checking the areas near University Circle for that reason, but there are some spots not far from there that can be rough, so do your due diligence.

I have friends in each spot and think they could help me build a great team.

More complex than it needs to be, I know, but what else is new when dealing with the City of Chicago...Nicolas, it looks like there is some "spot zoning" within the proximity and the first thing I would recommend would be reaching out to your Alderman.

We signed everything electronically but our county won't accept it.

The 2nd group can often be spotted via the credit report, and they are a lot less fun to host (late payments, asking for concessions, demanding, etc.)

E&O insurance, MLS fees, electronic lockbox fees, association dues, contract fees, every software agents use.Many of these fees could be close to doubling by the end of 2026.

Plenty exist for private lenders (which is what seller financing is) and can track payments and am tables and also do automatic electronic withdrawal (ACH debit) which helps improve the likelihood of getting paid promptly each month.

We are currently making roughly $1k per month house hacking all units and would earn a bit over $4k per month with all 6 units + garage spots rented out (Rental income - PITI). 

Their  numbers might be spot on, but you want to make sure you understand that yourself, not just taking there word for it.