The typical asking rate per listing is in the $0's per square foot per year. The Fairmount - Art Museum submarket is going through a decrease in rates. In the last 3 months, the median rate fell $28 per sqft per year. That's a 100% decrease in rent.
In the last 90 days, 7 listings have come on the market, which means new listings are probably going fast. You'll want to be prepared to make an offer immediately. 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 sqft. Most properties in this area are around 12 stories. Most buildings in this region were built in 1937 and are Class A.