The typical asking rate per listing is in the $40's per square foot per year. The Montclair region is seeing a a boost in rates. In the last 3 months, the median rate rose $46 per sqft per year. That's a Inf% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Montclair submarket has greater rates, and you'll have to negotiate above asking rent to be in this hot region.
In the last 90 days, 3 listings have come on the market, which means new listings are probably going fast. You'll want to be prepared to tour spaces as quick as possible. 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 130 sqft. Most buildings in this area were built in 1979 and are Class B.