On average, listings lease in the $10's per square foot per year. The Bellevue submarket is experiencing a a boost in rates. In the last 3 months, the median rate rose $1 per sqft per year. That's a 3% increase in rent.
In the last 90 days, 38 listings have come on the market, 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,810 sqft. Most properties in this area are approximately 2 stories. Most buildings in this region were built in 1984 and are Class C.