Compared to the rest of the Washington D.C. market, the Fairfax region has less expensive rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 31 listings have been posted online, which means listings most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 77% of the available leases in the Fairfax 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 1,510 sqft. Most buildings in this market are approximately 3 stories. Most buildings in this market were built in 1985 and are Class B.