On average, listings lease in the $20's per square foot per year. The Falls Church submarket 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.
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 discounted region.
In the last 90 days, 1 listings have come on the market, which means spaces most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 1,000% of the available space in the Falls Church are subleases, so you might be able to sign a shorter term by taking over a previous lease. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,050 sqft. Most buildings in this region are close to 2 floors. Most buildings in this market were built in 1980 and are Class B.