Most listings are in the $20's per square foot per year. The Simi Valley region is experiencing a a rise in rates. In the last 3 months, the median rate rose $11 per sqft per year. That's a 79% increase in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Simi Valley submarket has smaller rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 11 listings have come on the market, which means office spaces are probably going fast. You'll want to be prepared to tour spaces as quick as possible. About 100% of the office spaces in the Simi Valley are subleases, so you might be able to snag a great spot on a short term. 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 930 sqft. Most properties in this market are around 2 stories. Most buildings in this region were built in 1987 and are Class B.