Most listings are in the $20's per square foot per year. The Durham County submarket is going through a decline in rates. In the last 3 months, the median rate decreased $1 per sqft per year. That's a 4% decline in rent.
Compared to the rest of the The Triangle market, the Durham County submarket has less expensive rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 70 listings have come on the market, so you'll want to check back regularly for new listings. About 3% of the office spaces in the Durham 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 1,880 sqft. Most buildings in this region are close to 3 stories. Most buildings in this region were built in 1995 and are Class A.