The typical asking rate per listing is in the $20's per square foot per year. The San Dimas region is seeing a a rise in rates. In the last 3 months, the median rate went up $3 per sqft per year. That's a 13% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the San Dimas submarket has less expensive rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 25 listings have been made available, which means listings might be leasing quickly. 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.
The standard measurement for office space in this area is around 1,730 sqft. Most properties in this area are around 2 floors. Most buildings in this market were built in 1989 and are Class B.