Most listings are in the $20's per square foot per year. The Petaluma region is experiencing a decrease in rates. In the last 3 months, the median rate decreased $5 per sqft per year. That's a 15% decrease in rent.
Compared to the rest of the Bay Area market, the Petaluma region has smaller rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 31 listings have come on the market, which means listings are probably going fast. You'll want to be prepared to make an offer immediately. About 87% of the office spaces in the Petaluma are subleases, so you might be able to sign a shorter term by taking over a previous lease. 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 1,860 sqft. Most buildings in this area are approximately 2 stories. Most buildings in this area were built in 1990 and are Class A.