Most listings are in the $20's per square foot per year. The Maine submarket is going through a a rise in rates. In the last 3 months, the median rate went up $0 per sqft per year. That's a 2% rise in rent.
In the last 90 days, 192 listings have been listed, so you'll want to check back regularly for new listings. About 4% of the available space in the Maine 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 on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,000 sqft. Most properties in this market are around 2 floors. Most buildings in this area were built in 1900 and are Class Class B.