The typical asking rate per listing is in the $20's per square foot per year. The Rohnert Park region is going through a a boost in rates. In the last 3 months, the median rate increased $23 per sqft per year.
Compared to the rest of the Bay Area market, the Rohnert Park submarket has smaller rates, so you should have no trouble finding a great deal in this undervalued submarket.
In the last 90 days, 10 listings have been posted online, which means leases most likley are going fast. You'll want to be prepared to make an offer immediately. About 170% of the available leases in the Rohnert Park 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.
Even though the median size is 2,980 sqft, there are still 0 new availabilities below 2,000 sqft. Most buildings in this market are close to 1 stories. Most buildings in this market were built in 1985 and are Class B.