She will either take you seriously and move out, or she will show up in court with no defensible position and be forced out.The lease says she is responsible for electricity, but the former owner and property manager sets a precedent by paying it.

In Upstate NY we are held hostage by our electric and gas company so you never know if you will get a $120 electric/gas bill or a $3,000 bill.

If you don't have it you can call your insurance company and ask them to email you the declarations pageRecent Mortgage Statement:2 Different Utility Bills: Gas, Electric, Cell Phone Bill, Cable, Garbage, any two utility bills.Copy of Mortgage Note all pages: Was included in your closing documents when you purchased the home.

Add another $20 a month for that.Add in HOA fees ($300 a month; shown in your link), Gas, electricity, high-speed internet, water, trash and snow removal. 

Electrical, plumbing, the list could go on and on.

The building stock is like all the other Chicago urban core burbs, so expect lots of 1950's and 60's construction with galvanized pipes, flat roofs, boilers and outdated electrical.

What kind of electrical panel does it have?

Check how many electrical meters there are, and if there is one for the common area. 

Assets identified in this study include:Bathroom Fixtures: Bathtubs, vanities, showers and toiletsStructural Components: Drywall, wood framing and interior partitionsBuilding systems: water heater, electrical distribution, HVAC, plumbingInterior Construction: Wood flooring, stairs, ceramic tileSmoke detectorsThis engineering-based cost segregation study included the following methodology:Physical Inspection through a site visitDocumentation review including architectural plans, accounting records and construction documentsA cost analysis which utilizes engineering principles in order to allocate costs to their applicable asset classificationsCalculation of the depreciation schedule using MACRSAs a reminder, bonus depreciation started to phase out in 2023.

I buy supplies, and keep up with pricing, do repairs, except for electrical, plumbing and A/C.