Compared to the rest of the Bay Area market, the Rohnert Park submarket has less expensive rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 46 listings have been made available, so you'll want to check back regularly for new listings. 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 1,500 sqft. Most buildings in this area are around 1 stories. Most buildings in this region were built in 1986 and are Class B.