On average, listings lease in the $20's per square foot per year. The Bon Air submarket is going through a an increase in rates. In the last 3 months, the median rate went up $2 per sqft per year. That's a 8% rise in rent.
In the last 90 days, 5 listings have been made available, which means office spaces most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. About 60% of the office spaces in the Bon Air 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 available, 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 buildings in this market are approximately 2 stories. Most buildings in this region were built in 1987 and are Class B.