The typical asking rate per listing is in the $10's per square foot per year. The Westbrook submarket is going through a a boost in rates. In the last 3 months, the median rate increased $0 per sqft per year. That's a 1% increase in rent.
In the last 90 days, 4 listings have been listed, which means office spaces are probably leasing quickly. You'll want to be prepared to tour spaces as quick as possible. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,450 sqft. Most buildings in this region are around 2 stories. Most buildings in this area were built in 1900 and are Class Class B.