Agents have access to the MLS, and there are fewer rentals in the MLS than you'd find on sites like craigslist and westside rentals. Usually, we can find single family homes and higher end rentals, where the home owner used a realtor to help lease it. We generally can't help with lower cost apartments at bigger buildings, where a management company owns all the units.
So, if you're looking for a single family home for more than $2,500/mo, I can probably help (or at least send you a list of what's available in the MLS).
There's no real down side to using a realtor, since any commission we make is paid by the owner/seller - not by you.
Send me an email with your needs and I will gladly run a quick search for you and send you what's available. BenV@RodeoRE.com. You can also call me at (310)926-2386.