The typical asking rate per listing is in the $20's per square foot per year. The Portsmouth County submarket is going through a an increase in rates. In the last 3 months, the median rate rose $2 per sqft per year. That's a 11% increase in rent.
In the last 90 days, 26 listings have been posted online, which means new availabilities most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 73% of the listings in the Portsmouth County 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.
Even though the median size is 7,810 sqft, there are still 0 office spaces below 2,000 sqft. Most properties in this market are close to 2 floors. Most buildings in this region were built in 1984 and are Class B.