Compared to the rest of the Metropolitan Los Angeles market, the West Covina submarket has greater rates, and you'll need to make a great offer to be in this hot region.
In the last 90 days, 19 listings have come on the market, which means listings most likley are leasing quickly. You'll want to be prepared to make an offer immediately. 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 1,600 sqft. Most buildings in this area are around 2 stories. Most buildings in this area were built in 1980 and are Class B.