Otherwise it is UNPERMITTED taking a note by the appraiser as added on W/o a permit.

That would certainly provide added leverage should problems arise with bookkeeping, receipts, estimates, etc.

@Jennie Berger gave you the whole kit & caboodle on Chicago zoning so I don't have a ton to ad, however, I'd highly encourage you to engage an architect like @Samuel Pavlovcik or @Prashanth Mahakali, both are awesome local Chicago resources.

I have some concrete pads in the back of some of my homes, and I have added Costco type storage units to rent it out.

I'm currently adding all of my numbers for a 20-unit apartment building in for a test, and then I'll bring my other 90+ units.

Just adding pets alone really helped boost renting. 

I am good at Tik Tok ads and Facebook ads, this works for buyers but not sure what works best for listings.

EX: I ran a few real estate ads targeting real estate agents on FB. as a test since I never did an ads before.

Every state is different but what if you added additional egress doors/staircases? 

After adding those four items back in, it brings the complex to making around $6,500.