The typical asking rate per listing is in the $0's per square foot per year. The Elburn region is going through a decline in rates. In the last 3 months, the median rate fell $32 per sqft per year. That's a 100% decrease in rent.
In the last 90 days, 1 listings have been made available, which means leases are probably going fast. You'll want to be prepared to make an offer immediately. 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 sqft. Most buildings in this market are approximately 2 stories.