Compared to the rest of the Silicon Valley market, the Belmont region has higher rates, and you'll have to negotiate above asking rent to be in this hot region.
In the last 90 days, 11 listings have been made available, which means office spaces are probably going fast. You'll want to be prepared to make an offer immediately. 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 2,490 sqft. Most properties in this area are close to 4 stories. Most buildings in this market were built in 2000 and are Class B.