Most listings are in the $30's per square foot per year. The Costa Mesa submarket is experiencing a a rise in rates. In the last 3 months, the median rate increased $1 per sqft per year. That's a 4% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Costa Mesa submarket has lower rates, so you should have no trouble finding a great deal in this discounted submarket.
In the last 90 days, 62 listings have been made available, so you'll want to check back regularly for new listings. About 3% of the available space in the Costa Mesa are subleases, so you will probably have to focus your search on direct office leases. 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 2,080 sqft. Most buildings in this region are around 2 stories. Most buildings in this area were built in 1983 and are Class A.