Most listings are in the $20's per square foot per year. The Mantua region is seeing a a rise in rates. In the last 3 months, the median rate went up $29 per sqft per year.
Compared to the rest of the Washington D.C. market, the Mantua region has lower rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 0 listings have come on the market, which means office spaces might be leasing quickly. You'll want to be prepared to tour spaces as quick as possible. About Inf% of the available leases in the Mantua are subleases, so you might be able to find a shorter term or below market rent. 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 1,130 sqft.