Most listings are in the $30's per square foot per year. The El Monte region is going through a an increase in rates. In the last 3 months, the median rate went up $31 per sqft per year.
Compared to the rest of the Metropolitan Los Angeles market, the El Monte region has smaller rates, so you should have no trouble finding a great deal in this undervalued region.
In the last 90 days, 3 listings have been posted online, which means listings might be going fast. You'll want to be prepared to tour spaces as quick as possible. About 400% of the office spaces in the El Monte are subleases, so you might be able to sign a shorter term by taking over a previous lease. 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 1,080 sqft. Most properties in this region are close to 2 stories. Most buildings in this area were built in 1974 and are Class B.