On average, listings lease in the $30's per square foot per year. The Manassas Park region is going through a a boost in rates. In the last 3 months, the median rate went up $0 per sqft per year. That's a 1% increase in rent.
Compared to the rest of the Washington D.C. market, the Manassas Park region has more expensive rates, and you'll need to make a great offer to be in this hot submarket.
In the last 90 days, 12 listings have been made available, which means spaces are probably going fast. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 200 sqft. Most buildings in this area were built in 1983 and are Class B.