Most listings are in the $10's per square foot per year. The Mendocino submarket is seeing a decrease in rates. In the last 3 months, the median rate fell $2 per sqft per year. That's a 12% decline in rent.
In the last 90 days, 3 listings have been posted online, which means office spaces are probably leasing quickly. You'll want to be prepared to make an offer immediately. About 167% of the available leases in the Mendocino 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 740 sqft. Most properties in this market are around 1 floors. Most buildings in this area were built in 1988.