Most listings are in the $10's per square foot per year. The Cascades region is seeing a decline in rates. In the last 3 months, the median rate decreased $8 per sqft per year. That's a 33% decrease in rent.
Compared to the rest of the Washington D.C. market, the Cascades submarket has less expensive rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 3 listings have been made available, which means leases are probably 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 1,000 sqft. Most properties in this market are close to 3 floors. Most buildings in this area were built in 2002 and are Class B.