On average, listings lease in the $10's per square foot per year. The Oakbrook Terrace submarket is going through a decline in rates. In the last 3 months, the median rate fell $6 per sqft per year. That's a 24% decline in rent.
Compared to the rest of the Chicagoland market, the Oakbrook Terrace submarket has less expensive rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 39 listings have come on the market, which means leases most likley are leasing quickly. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
Even though the median size is 4,410 sqft, there are still 0 new listings below 2,000 sqft. Most properties in this region are approximately 3 stories. Most buildings in this market were built in 1985 and are Class A.