On average, listings lease in the $20's per square foot per year. The Dayton submarket is going through a decline in rates. In the last 3 months, the median rate fell $6 per sqft per year. That's a 19% decrease in rent.
In the last 90 days, 25 listings have come on the market, which means office spaces most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 12% of the office spaces in the Dayton are subleases, so you might be able to find a shorter term or below market rent. 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 1,450 sqft. Most properties in this region are around 2 stories. Most buildings in this region were built in 1971 and are Class B.