The typical asking rate per listing is in the $20's per square foot per year. The Riverside region is going through a a rise in rates. In the last 3 months, the median rate rose $29 per sqft per year.
Compared to the rest of the Metropolitan Los Angeles market, the Riverside region has less expensive rates, so you should have no trouble finding a great deal in this depreciated submarket.
In the last 90 days, 65 listings have come on the market, so you'll want to check back regularly for new listings. About 78% of the available space in the Riverside are subleases, so you might be able to find a shorter term or below market rent. 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 3,150 sqft, there are still 0 office spaces below 2,000 sqft. Most buildings in this region are approximately 2 stories. Most buildings in this region were built in 1990 and are Class C.