On average, listings lease in the $10's per square foot per year. The Barrington submarket is going through a decline in rates. In the last 3 months, the median rate fell $3 per sqft per year. That's a 14% decrease in rent.
Compared to the rest of the Chicagoland market, the Barrington submarket has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 42 listings have come on the market, so you'll want to check back regularly for new listings. There aren't many listings below 2,000 square feet on the market, 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 properties in this market are approximately 2 stories. Most buildings in this area were built in 1984 and are Class B.