Compared to the rest of the Washington D.C. market, the Fredericksburg submarket has less expensive rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 25 listings have been listed, which means listings most likley are leasing quickly. You'll want to be prepared to make an offer immediately. 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 1,370 sqft. Most buildings in this area are approximately 2 stories. Most buildings in this market were built in 1984 and are Class B.