The typical asking rate per listing is in the $20's per square foot per year. The Rancho Santa Margarita submarket is going through a an increase in rates. In the last 3 months, the median rate went up $1 per sqft per year. That's a 3% increase in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Rancho Santa Margarita region has smaller rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 21 listings have come on the market, which means spaces are probably going fast. You'll want to be prepared to make an offer immediately. 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 850 sqft. Most buildings in this area are approximately 2 floors. Most buildings in this area were built in 2002 and are Class A.