Most listings are in the $10's per square foot per year. The Lewiston region is experiencing a a boost in rates. In the last 3 months, the median rate rose $3 per sqft per year. That's a 15% increase in rent.
In the last 90 days, 2 listings have been made available, which means spaces most likley are going fast. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,500 sqft. Most properties in this market are close to 2 floors. Most buildings in this area were built in 1883 and are Class Class B.