The typical asking rate per listing is in the $20's per square foot per year. The Orange region is going through a an increase in rates. In the last 3 months, the median rate rose $5 per sqft per year. That's a 22% rise in rent.
In the last 90 days, 4 listings have come on the market, which means new listings are probably 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 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 2,350 sqft. Most properties in this area are around 2 stories. Most buildings in this market were built in 1984 and are Class B.