The typical asking rate per listing is in the $10's per square foot per year. The Eau Claire region is going through a a rise in rates. In the last 3 months, the median rate went up $0 per sqft per year. That's a 2% rise in rent.
In the last 90 days, 9 listings have come on the market, which means new availabilities are probably leasing quickly. You'll want to be prepared to make an offer immediately. 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 1,310 sqft. Most properties in this region are around 2 stories. Most buildings in this region were built in 1978 and are Class B.