Most listings are in the $20's per square foot per year. The Charleston County region is experiencing a decline in rates. In the last 3 months, the median rate fell $3 per sqft per year. That's a 10% decline in rent.
In the last 90 days, 233 listings have come on the market, so you'll want to check back regularly for new listings. About 2% of the available space in the Charleston County are subleases, so you will probably have to consider a longer term lease. 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 buildings in this area are around 2 stories. Most buildings in this region were built in 1989 and are Class A.