Most listings are in the $0's per square foot per year. The Norwalk submarket is going through a decline in rates. In the last 3 months, the median rate fell $34 per sqft per year. That's a 100% decline in rent.
In the last 90 days, 2 listings have been listed, which means office spaces most likley are 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 market are close to 2 stories. Most buildings in this area were built in 1977 and are Class B.