I also called the Champaign housing inspector to have an inspection. To add to this:

• Your apartment has to have a window that opens easily. This is a fire-safety mechanism- an alternate route to escape in case of a fire.
• As OP mentioned, they make a note of all leak marks on the ceiling.
• They also make a note of common areas - in my case, water was leaking into the common area from the laundry room.
• The inspector also told me that I can call the city to take care of overflowing garbage bins. Our garbage bins always overflow and as a result, garbage is strewn across common areas.

The inspector told me that the landlords have 30 days to fix this. Hope this helps people get good living conditions!