Compared to the rest of the Metropolitan Los Angeles market, the Corona submarket has smaller rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 47 listings have come on the market, so you'll want to check back regularly for new listings. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,900 sqft. Most properties in this region are around 2 stories. Most buildings in this area were built in 2005 and are Class B.