On average, listings lease in the $30's per square foot per year. The Mercer Island region is experiencing a decrease in rates. In the last 3 months, the median rate fell $13 per sqft per year. That's a 27% decline in rent.
Compared to the rest of the Seattle Metropolitan Area market, the Mercer Island submarket has higher rates, and you'll have to negotiate above asking rent to be in this hot submarket.
In the last 90 days, 1 listings have been listed, which means new availabilities are probably leasing quickly. You'll want to be prepared to tour spaces as quick as possible. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 980 sqft. Most buildings in this region are approximately 2 floors. Most buildings in this region were built in 1984 and are Class B.