The typical asking rate per listing is in the $30's per square foot per year. The Azusa region is going through a an increase in rates. In the last 3 months, the median rate rose $31 per sqft per year. That's a Inf% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Azusa submarket has smaller rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 4 listings have been listed, which means new availabilities most likley are leasing quickly. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
Even though the median size is 9,530 sqft, there are still 0 leases below 2,000 sqft. Most properties in this region are close to 2 stories. Most buildings in this region were built in 1985 and are Class C.