Most listings are in the $10's per square foot per year. The Manchester submarket is going through a decrease in rates. In the last 3 months, the median rate decreased $2 per sqft per year. That's a 9% decline in rent.
In the last 90 days, 4 listings have been listed, which means spaces 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 1,060 sqft. Most properties in this market are close to 2 stories. Most buildings in this region were built in 1930 and are Class B.