The typical asking rate per listing is in the $10's per square foot per year. The Newtown region is going through a a rise in rates. In the last 3 months, the median rate went up $3 per sqft per year. That's a 20% rise in rent.
Compared to the rest of the Fairfield market, the Newtown submarket has lower rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 4 listings have been posted online, which means listings most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. 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 1,320 sqft. Most properties in this market are approximately 2 floors. Most buildings in this area were built in 1928 and are Class A.