On average, listings lease in the $30's per square foot per year. The West Side submarket is going through a a boost in rates. In the last 3 months, the median rate increased $30 per sqft per year.
Compared to the rest of the Chicagoland market, the West Side submarket has more expensive rates, and you'll need to pay a premium to be in this hot submarket.
In the last 90 days, 40 listings have been listed, which means leases most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 140% of the available leases in the West Side are subleases, so you might be able to find a shorter term or below market rent. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,410 sqft. Most properties in this area are approximately 3 floors. Most buildings in this region were built in 1925 and are Class B.