Most listings are in the $20's per square foot per year. The East Los Angeles submarket is experiencing a a boost in rates. In the last 3 months, the median rate rose $3 per sqft per year. That's a 11% rise in rent.
Compared to the rest of the Metropolitan Los Angeles market, the East Los Angeles submarket has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 2 listings have been posted online, which means leases most likley are going fast. You'll want to be prepared to make an offer immediately. About 150% of the available space in the East Los Angeles 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 posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,000 sqft. Most properties in this market are close to 1 floors. Most buildings in this market were built in 1951 and are Class B.