Here's the City link for you to reference. https://www.chicago.gov/city/en/depts/doh/provdrs/homeowners...1) ADU regulations specifically exclude Short-Term Rentals so don't do it if the intention is to short-term rental. 2) The ceiling height oh 6'10" is almost guaranteed to trigger digging a basement if you want to formalize as an ADU unit, especially if that height is further reduced by pipes or HVAC. 3)Ingress/egress is an issue for renting, as is that any bedroom also will need two (ie operable window/doorway).

Your main issues will be eggress, as usual in a basement.

I'm surprised at the responses here, and think there could possibly be confusion and an assumption that might be created in the responses.To provide a based answer, my question to @Zoe Brennan is, are you working on the investment opportunity with your time as well? 

Please note the information provided below is a layman's definition designed to provide a basic understanding for the general audience.

You don't need to know everything to get started; you need a foundation to build on, and the rest will come through experience and then refining your education.You can build a basic understanding of investing in 3-6 months.

You don't need to know everything to get started; you need a foundation to build on, and the rest will come through experience and then refining your education.You can build a basic understanding of investing in 3-6 months.

You don't need to know everything to get started; you need a foundation to build on, and the rest will come through experience and then refining your education.You can build a basic understanding of investing in 3-6 months.

But I think you are asking for a standard timeline for a basic transaction @Kiryl Ulanovich. 

@Peter Mckernan Copy.... it's a "% based payment" off scope of work. 

Please note the information provided below is a layman's definition designed to provide a basic understanding for the general audience.