Most listings are in the $20's per square foot per year. The Warrenville region is experiencing a decline in rates. In the last 3 months, the median rate fell $2 per sqft per year. That's a 7% decrease in rent.
Compared to the rest of the Chicagoland market, the Warrenville region has less expensive rates, so you should have no trouble finding a great deal in this undervalued submarket.
In the last 90 days, 9 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 278% of the available leases in the Warrenville 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 1,500 sqft. Most buildings in this market are approximately 2 stories. Most buildings in this region were built in 1999 and are Class B.