The typical asking rate per listing is in the $20's per square foot per year. The Mystic region is experiencing a an increase in rates. In the last 3 months, the median rate went up $25 per sqft per year.
In the last 90 days, 2 listings have been made available, which means listings might be leasing quickly. You'll want to be prepared to make an offer immediately. About 50% of the listings in the Mystic are subleases, so you might be able to find a shorter term or below market rent. 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 900 sqft. Most buildings in this area are close to 1 floors. Most buildings in this region were built in 1920.