On average, listings lease in the $20's per square foot per year. The Manassas County region is seeing a decline in rates. In the last 3 months, the median rate decreased $2 per sqft per year. That's a 8% decrease in rent.
In the last 90 days, 30 listings have been listed, which means office spaces are probably going fast. You'll want to be prepared to make an offer immediately. About 7% of the available leases in the Manassas 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.
The standard measurement for office space in this area is around 2,080 sqft. Most properties in this market are approximately 2 stories. Most buildings in this region were built in 1988 and are Class B.