Compared to the rest of the San Diego market, the San Marcos region has lower rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 31 listings have been made available, which means office spaces 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 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 1,490 sqft. Most properties in this region are around 2 floors. Most buildings in this market were built in 1984 and are Class B.