On average, listings lease in the $30's per square foot per year. The Pomona submarket is going through a an increase in rates. In the last 3 months, the median rate went up $12 per sqft per year. That's a 62% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the Pomona submarket has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 16 listings have been made available, which means spaces might be going fast. 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 1,500 sqft. Most buildings in this market are approximately 2 floors. Most buildings in this market were built in 1983 and are Class B.