On average, listings lease in the $0's per square foot per year. The Rialto region is going through a decline in rates. In the last 3 months, the median rate fell $35 per sqft per year. That's a 100% decline in rent.
In the last 90 days, 3 listings have been posted online, which means spaces most likley are 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.
Even though the median size is 3,000 sqft, there are still 0 spaces below 2,000 sqft. Most buildings in this area are around 1 stories. Most buildings in this region were built in 2000 and are Class A.