On average, listings lease in the $30's per square foot per year. The Claremont submarket is going through a a rise in rates. In the last 3 months, the median rate increased $6 per sqft per year. That's a 24% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Claremont region has lower rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 2 listings have come on the market, which means leases are probably leasing quickly. You'll want to be prepared to make an offer immediately. 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 610 sqft. Most buildings in this market are approximately 1 stories. Most buildings in this region were built in 2008 and are Class B.