Most listings are in the $20's per square foot per year. The Greater Boston region is going through a an increase in rates. In the last 3 months, the median rate increased $1 per sqft per year. That's a 3% increase in rent.
In the last 90 days, 1051 listings have been made available, so you'll want to check back regularly for new listings. About 4% of the office spaces in the Greater Boston are subleases, so you will probably need to sign a longer term lease with the landlord directly. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
Even though the median size is 3,850 sqft, there are still 0 office spaces below 2,000 sqft. Most properties in this area are close to 2 floors. Most buildings in this region were built in 1965 and are Class A.