Most listings are in the $20's per square foot per year. The Berkeley County submarket is going through a a rise in rates. In the last 3 months, the median rate increased $1 per sqft per year. That's a 7% rise in rent.
In the last 90 days, 3 listings have been made available, which means new availabilities are probably 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 1,790 sqft. Most buildings in this market are approximately 1 stories. Most buildings in this region were built in 1996 and are Class A.