The typical asking rate per listing is in the $30's per square foot per year. The Loudoun County submarket is seeing a a boost in rates. In the last 3 months, the median rate rose $7 per sqft per year. That's a 28% increase in rent.
In the last 90 days, 34 listings have been listed, which means new availabilities are probably leasing quickly. You'll want to be prepared to make an offer immediately. About 3% of the office spaces in the Loudoun County are subleases, so you will probably need to consider the implications of signing a direct lease with the building. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
Even though the median size is 3,980 sqft, there are still 0 new availabilities below 2,000 sqft. Most properties in this market are close to 1 stories. Most buildings in this area were built in 2000 and are Class A.