The typical asking rate per listing is in the $30's per square foot per year. The Rancho Santa Margarita region is experiencing a a rise in rates. In the last 3 months, the median rate rose $3 per sqft per year. That's a 11% increase in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Rancho Santa Margarita submarket has lower rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 10 listings have been listed, which means new availabilities most likley are leasing quickly. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 1,150 sqft. Most properties in this market are close to 2 floors. Most buildings in this area were built in 2002 and are Class A.