On average, listings lease in the $20's per square foot per year. The Bon Air region is going through a a rise in rates. In the last 3 months, the median rate increased $2 per sqft per year. That's a 8% rise in rent.
In the last 90 days, 5 listings have come on the market, which means office spaces most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 80% of the available space in the Bon Air 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 1,100 sqft. Most properties in this market are close to 2 stories. Most buildings in this region were built in 1987 and are Class B.