Compared to the rest of the Bay Area market, the Novato submarket has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 40 listings have been posted online, which means new availabilities most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. About 8% of the listings in the Novato are subleases, so you will probably need to sign a longer term lease with the landlord directly. 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 1,990 sqft. Most properties in this market are close to 2 floors. Most buildings in this market were built in 1987 and are Class B.