The typical asking rate per listing is in the $10's per square foot per year. The Summerville region is going through a a rise in rates. In the last 3 months, the median rate increased $18 per sqft per year.
In the last 90 days, 10 listings have been listed, which means office spaces might be going fast. You'll want to be prepared to tour spaces as quick as possible. About 20% of the available leases in the Summerville 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,180 sqft. Most buildings in this market are approximately 2 floors. Most buildings in this area were built in 1996 and are Class A.