Compared to the rest of the Chicagoland market, the River Forest region has smaller rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 1 listings have been posted online, which means listings are probably leasing quickly. You'll want to be prepared to tour spaces as quick as possible. There aren't many listings below 2,000 square feet available, 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.