The typical asking rate per listing is in the $20's per square foot per year. The Fullerton region is seeing a a boost in rates. In the last 3 months, the median rate went up $3 per sqft per year. That's a 12% increase in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Fullerton region has smaller rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 29 listings have been listed, which means spaces might be going fast. You'll want to be prepared to make an offer immediately. 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 700 sqft. Most buildings in this area are close to 2 floors. Most buildings in this region were built in 1975 and are Class B.