The typical asking rate per listing is in the $20's per square foot per year. The Butler County region is going through a an increase in rates. In the last 3 months, the median rate rose $29 per sqft per year.
In the last 90 days, 14 listings have been made available, which means listings are probably leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 7% of the available space in the Butler County are subleases, so you will probably have to focus your search on direct office leases. 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 240 sqft. Most properties in this market are close to 1 floors. Most buildings in this area were built in 2002 and are Class B.