The typical asking rate per listing is in the $10's per square foot per year. The Johnston region is experiencing a decline in rates. In the last 3 months, the median rate fell $1 per sqft per year. That's a 5% decrease in rent.
In the last 90 days, 6 listings have been listed, which means new listings 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 1,720 sqft. Most buildings in this region are around 1 floors. Most buildings in this region were built in 2005 and are Class B.