Most listings are in the $30's per square foot per year. The Ontario submarket is experiencing a an increase in rates. In the last 3 months, the median rate rose $2 per sqft per year. That's a 5% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Ontario region has smaller rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 71 listings have come on the market, so you'll want to check back regularly for new listings. About 1% of the available space in the Ontario are subleases, so you will probably have to focus your search on direct office leases. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
Even though the median size is 3,200 sqft, there are still 0 listings below 2,000 sqft. Most properties in this region are close to 2 floors. Most buildings in this region were built in 2000 and are Class A.