Most listings are in the $30's per square foot per year. The Greater Portland submarket is experiencing a an increase in rates. In the last 3 months, the median rate went up $32 per sqft per year.
In the last 90 days, 541 listings have come on the market, so you'll want to check back regularly for new listings. About 85% of the listings in the Greater Portland 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 available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,860 sqft. Most buildings in this area are approximately 2 floors. Most buildings in this area were built in 1985 and are Class A.