Most listings are in the $40's per square foot per year. The Danville region is seeing a a rise in rates. In the last 3 months, the median rate increased $17 per sqft per year. That's a 63% rise in rent.
Compared to the rest of the East Bay market, the Danville region has smaller rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 5 listings have been posted online, which means leases 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 580 sqft. Most properties in this region are approximately 2 floors. Most buildings in this market were built in 1982 and are Class B.