On average, listings lease in the $10's per square foot per year. The Irving Park submarket is experiencing a a boost in rates. In the last 3 months, the median rate rose $16 per sqft per year.
Compared to the rest of the Chicagoland market, the Irving Park region has smaller rates, so you should have no trouble finding a great deal in this undervalued submarket.
In the last 90 days, 0 listings have been listed, which means new availabilities most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About Inf% of the office spaces in the Irving Park are subleases, so you might be able to snag a great spot on a short term. 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 1,500 sqft. Most buildings in this market are around 2 floors. Most buildings in this region were built in 1952 and are Class B.