Most listings are in the $10's per square foot per year. The Barrington region is going through a decrease in rates. In the last 3 months, the median rate fell $4 per sqft per year. That's a 19% decline in rent.
Compared to the rest of the Chicagoland market, the Barrington submarket has smaller rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 40 listings have been listed, which means new listings most likley are 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 1,260 sqft. Most buildings in this market are around 2 stories. Most buildings in this area were built in 1980 and are Class B.