The typical asking rate per listing is in the $40's per square foot per year. The Coronado region is going through a a rise in rates. In the last 3 months, the median rate rose $48 per sqft per year.
Compared to the rest of the San Diego market, the Coronado region has higher rates, and you'll need to make a great offer to be in this hot region.
In the last 90 days, 1 listings have been made available, which means new availabilities 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 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 600 sqft. Most buildings in this area are around 3 floors. Most buildings in this market were built in 2005 and are Class B.