Most listings are in the $10's per square foot per year. The Clinton County submarket is seeing a an increase in rates. In the last 3 months, the median rate went up $16 per sqft per year.
In the last 90 days, 4 listings have been listed, which means new availabilities are probably leasing quickly. You'll want to be prepared to make an offer immediately. About 25% of the available leases in the Clinton County are subleases, so you might be able to sign a shorter term by taking over a previous lease. 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 2,000 sqft. Most properties in this region are approximately 1 stories. Most buildings in this market were built in 2006.