On average, listings lease in the $30's per square foot per year. The Dayton region is going through a a rise in rates. In the last 3 months, the median rate rose $10 per sqft per year. That's a 47% increase in rent.
In the last 90 days, 18 listings have come on the market, which means leases might be leasing quickly. You'll want to be prepared to make an offer immediately. About 6% of the listings in the Dayton are subleases, so you will probably need to consider the implications of signing a direct lease with the building. 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 2,260 sqft. Most properties in this region are approximately 3 floors. Most buildings in this area were built in 1971 and are Class B.