Most listings are in the $20's per square foot per year. The Durham region is experiencing a decline in rates. In the last 3 months, the median rate fell $1 per sqft per year. That's a 3% decline in rent.
Compared to the rest of the The Triangle market, the Durham region has smaller rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 55 listings have been listed, so you'll want to check back regularly for new listings. About 4% of the office spaces in the Durham are subleases, so you will probably need to sign a longer term lease with the landlord directly. 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 1,500 sqft. Most buildings in this area are close to 2 stories. Most buildings in this area were built in 1995 and are Class A.