We rent a car when we fly out of LAX. You've got a 24 hour window for the car rental. Sometimes, we pick it up the day before. With a late night departure, we have driven up in the afternoon and had dinner somewhere near the airport before dropping it off. It's the same on the return home. You've got 24 hours, so it's possible to drive home, then a few hours later or the next day, take it to the drop off point. I'm typically able to rent a car for a one way rental for roughly $50. Gassing it adds a few dollars.
Here's a past discussion: http://www.flyertalk.com/forum/los-a...-lax-back.html