The typical asking rate per listing is in the $20's per square foot per year. The Wilmington submarket is going through a an increase in rates. In the last 3 months, the median rate went up $2 per sqft per year. That's a 9% rise in rent.
In the last 90 days, 58 listings have been listed, so you'll want to check back regularly for new listings. About 2% of the available space in the Wilmington are subleases, so you will probably have to consider a longer term lease. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,990 sqft. Most buildings in this region are approximately 1 floors. Most buildings in this market were built in 1994 and are Class B.