The typical asking rate per listing is in the $30's per square foot per year. The Whittier region is seeing a an increase in rates. In the last 3 months, the median rate increased $4 per sqft per year. That's a 14% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Whittier submarket has smaller rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 5 listings have been listed, which means new availabilities most likley are going fast. You'll want to be prepared to make an offer immediately. About 40% of the available leases in the Whittier are subleases, so you might be able to snag a great spot on a short term. 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 900 sqft. Most buildings in this area are close to 2 floors. Most buildings in this area were built in 1974 and are Class B.