On average, listings lease in the $60's per square foot per year. The Columbia Heights submarket is going through a a boost in rates. In the last 3 months, the median rate increased $63 per sqft per year.
In the last 90 days, 4 listings have come on the market, which means spaces most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. 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 910 sqft. Most properties in this market are approximately 2 stories. Most buildings in this market were built in 1980 and are Class C.