The typical asking rate per listing is in the $30's per square foot per year. The Butler County submarket is going through a a boost in rates. In the last 3 months, the median rate went up $3 per sqft per year. That's a 9% rise in rent.
In the last 90 days, 26 listings have been made available, which means new listings most likley are going fast. You'll want to be prepared to make an offer immediately. About 4% of the available leases in the Butler County are subleases, so you will probably need to sign a longer term lease with the landlord directly. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
Even though the median size is 5,120 sqft, there are still 0 leases below 2,000 sqft. Most properties in this area are close to 3 floors. Most buildings in this market were built in 2003 and are Class A.