In the last 90 days, 10128 listings have been made available, so you'll want to check back regularly for new listings. About 5% of the available leases in the California are subleases, so you will probably have to focus your search on direct office leases. 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 2,300 sqft. Most buildings in this area are around 2 floors. Most buildings in this region were built in 1958 and are Class B.