Compare to other 4 bedroom rentals  with similar square footage in the area.  

The unit is brand new and is too big for the 1200 square foot townhouse, so it heats up the space quickly and then shuts off.  

What is a big Red Flag?

The education and exams have more to do with proper disclosures, discrimination, red lining, etc. than with how to buy and sell. 

Based a price per square foot of recent comps in the same neighborhood, the ARV should be somewhere around $350,000 with a rental potential of $1400-$1500/mo.

I'd also add Edgewater, Lincoln Square, Logan Square, and Rogers Park to the neighborhoods she listed.  

See what you can find out then talk to a contractor about bringing it up to code.Generally buyers don't just look at square feet.

The square footage of the apartments is substantially more than the store front.Thanks!

I always thought I did a good job of screening, gut checking, red flag observing – the usual seasoned Landlord stuff.

At the same time, if you are not already very familiar with what your ARV is, look at past sales in last 5 months (because rehab might take 30 days minimum), with in .5 miles, +/- 15% square footage, +/- 10 years, about same land size (or adjust).