In the last 90 days, 2 listings have been listed, which means office spaces are probably leasing quickly. You'll want to be prepared to make an offer immediately. 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 sqft. Most buildings in this market are around 2 stories. Most buildings in this area were built in 1870 and are Class B.