Most listings are in the $10's per square foot per year. The Butler submarket is going through a a rise in rates. In the last 3 months, the median rate increased $17 per sqft per year.
In the last 90 days, 2 listings have come on the market, which means office spaces most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. About 100% of the listings in the Butler 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 on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 950 sqft. Most properties in this area are approximately 2 stories. Most buildings in this region were built in 1964 and are Class B.