On average, listings lease in the $20's per square foot per year. The North Haven submarket is going through a an increase in rates. In the last 3 months, the median rate increased $8 per sqft per year. That's a 50% rise in rent.
In the last 90 days, 8 listings have been posted online, which means listings most likley are leasing quickly. 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 2,400 sqft. Most properties in this region are around 2 stories. Most buildings in this area were built in 1986 and are Class B.