Most listings are in the $20's per square foot per year. The Marlborough submarket is experiencing a a rise in rates. In the last 3 months, the median rate went up $4 per sqft per year. That's a 19% increase in rent.
Compared to the rest of the Greater Boston market, the Marlborough region has smaller rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 55 listings have been made available, so you'll want to check back regularly for new listings. 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 240 sqft. Most buildings in this market are close to 3 floors. Most buildings in this area were built in 1986 and are Class A.