What makes it an ADU or JADU vs just more rooms in the house are permits you file with the local city to make it an ADU as well as providing separate bath and cooking facilities and a separate entrance.

I think one important thing to point out is that 5 and 6 units are taxed like houses (residential) whereas 7 or more units in Cook County are taxed as commercial. 

I'd be cautious about excluding pets if you're concerned about vacancy.C) While much better tenants (very little wear and tear on your property, good for rent, pass background checks), there is a need for many STR amenities (security conscious with parking spaces and the home, have nice bed/sheets/cooking supplies/coffee maker, high speed internet a plus - having great TV wasn't a deal breaker for those we surveyed)D) Mixed input on the proximity. 

However, overall, Illinois taxes (especially in Cook/DuPage counties) are quite high relative to other states including Indiana.

Hamlet M and J Cooke properties, LLC

I know, it sounds irresponsible to not know exactly what one has purchased, however, this little portion of the property was tucked away behind a wall of trees and vegetation.  

Yes, Cook county is definitely on the hunt for every penny they can get their hands on.

You also need to think about how the tenant in the basement will cook.

@Daijamonet Cook I love this question!

If you go to the add on route(add a bedroom and a bathroom), you can think about the add on functioning like an attached “in law unit” with a hot plate for working professional to cook on, with that I would say rents about 900ish depending on the set up.