On average, listings lease in the $20's per square foot per year. The Manassas County submarket is going through a an increase in rates. In the last 3 months, the median rate increased $3 per sqft per year. That's a 14% rise in rent.
In the last 90 days, 29 listings have been made available, which means leases most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 21% of the available space in the Manassas County are subleases, so you might be able to find a shorter term or below market rent. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
Even though the median size is 2,700 sqft, there are still 0 office spaces below 2,000 sqft. Most buildings in this region are approximately 2 floors. Most buildings in this area were built in 1989 and are Class B.