The typical asking rate per listing is in the $20's per square foot per year. The Falls Church region is seeing a an increase in rates. In the last 3 months, the median rate increased $26 per sqft per year.
Compared to the rest of the Washington D.C. market, the Falls Church region has smaller rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 1 listings have been listed, which means leases 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 510 sqft. Most buildings in this region are close to 2 floors. Most buildings in this market were built in 1981 and are Class B.