Most listings are in the $0's per square foot per year. The El Cajon region is going through a decrease in rates. In the last 3 months, the median rate fell $21 per sqft per year. That's a 100% decline in rent.
In the last 90 days, 16 listings have been listed, which means new availabilities are probably 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 sqft. Most properties in this area are approximately 2 floors. Most buildings in this market were built in 1977 and are Class B.