Compared to the rest of the Washington D.C. market, the Warrenton region has less expensive rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 3 listings have been made available, which means office spaces most likley are leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About 833% of the available leases in the Warrenton 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,340 sqft. Most buildings in this market are approximately 3 stories. Most buildings in this region were built in 1991 and are Class A.