Most listings are in the $10's per square foot per year. The Janesville region is seeing a a boost in rates. In the last 3 months, the median rate rose $18 per sqft per year.
In the last 90 days, 31 listings have been made available, which means new listings are probably going fast. You'll want to be prepared to tour spaces as quick as possible. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,270 sqft. Most properties in this area are approximately 2 floors. Most buildings in this area were built in 1979 and are Class B.