On average, listings lease in the $30's per square foot per year. The Fairfax County region is seeing a decline in rates. In the last 3 months, the median rate fell $4 per sqft per year. That's a 11% decline in rent.
In the last 90 days, 234 listings have come on the market, so you'll want to check back regularly for new listings. About 3% of the available space in the Fairfax County are subleases, so you will probably have to consider a longer term lease. 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 2,930 sqft, there are still 0 office spaces below 2,000 sqft. Most properties in this area are around 4 stories. Most buildings in this region were built in 1987 and are Class A.