The typical asking rate per listing is in the $20's per square foot per year. The Ashburn region is experiencing a decline in rates. In the last 3 months, the median rate fell $3 per sqft per year. That's a 9% decrease in rent.
Compared to the rest of the Washington D.C. market, the Ashburn region has less expensive rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 22 listings have come on the market, which means listings are probably leasing quickly. You'll want to be prepared to make an offer immediately. 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 2,370 sqft. Most buildings in this market are around 2 floors. Most buildings in this region were built in 2001 and are Class A.