The typical asking rate per listing is in the $10's per square foot per year. The Mendocino submarket is seeing a a boost in rates. In the last 3 months, the median rate rose $17 per sqft per year.
In the last 90 days, 3 listings have been posted online, which means spaces are probably going fast. You'll want to be prepared to tour spaces as quick as possible. About 200% of the listings in the Mendocino are subleases, so you might be able to find a shorter term or below market rent. 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 690 sqft. Most properties in this market are approximately 1 floors. Most buildings in this market were built in 1988.