Most listings are in the $40's per square foot per year. The San Juan Capistrano region is going through a decrease in rates. In the last 3 months, the median rate decreased $5 per sqft per year. That's a 10% decline in rent.
Compared to the rest of the Metropolitan Los Angeles market, the San Juan Capistrano submarket has greater rates, and you'll have to negotiate above asking rent to be in this hot region.
In the last 90 days, 2 listings have been made available, which means new listings most likley are 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 2,210 sqft. Most properties in this area are approximately 2 stories. Most buildings in this area were built in 1989 and are Class B.