On average, listings lease in the $40's per square foot per year. The Bethesda region is experiencing a a rise in rates. In the last 3 months, the median rate increased $46 per sqft per year.
Compared to the rest of the Washington D.C. market, the Bethesda submarket has higher rates, and you'll need to pay a premium to be in this hot region.
In the last 90 days, 23 listings have come on the market, which means leases most likley are leasing quickly. You'll want to be prepared to make an offer immediately. About 65% of the available space in the Bethesda are subleases, so you might be able to snag a great spot on a short term. 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 2,500 sqft. Most buildings in this area are close to 10 stories. Most buildings in this area were built in 1980 and are Class A.