On average, listings lease in the $30's per square foot per year. The Falls Church submarket is experiencing a a rise in rates. In the last 3 months, the median rate rose $35 per sqft per year.
Compared to the rest of the Washington D.C. market, the Falls Church submarket has higher rates, and you'll have to negotiate above asking rent to be in this hot region.
In the last 90 days, 5 listings have come on the market, which means new listings most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. 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 540 sqft. Most properties in this market are around 1 stories. Most buildings in this area were built in 1980 and are Class B.