Since no one walks anywhere in LA, and since everything is about 1/2 an hour to 45 minutes away from everything else in LA, you will need to own a car. Might I also add here that LA is hot as you know what in the summer. If your car doesn't have air-conditioning, good luck arriving at meetings looking fresh!
As a working actor, you will be expected to drop what you are doing with one phone call from your agent, and head out the door 5 minutes later to go on an audition. This makes life a bit difficult if you have a full time job (which you will!) and if your job is at the Macy’s in the Valley, and your audition is in Santa Monica. That being said, if you have a reliable car, you won't be stressed. You can always keep a change of clothes (or two or three) in your car, along with a stack of different headshots and resumes, to pass out as you need.
You will always have your air-conditioner on high, and you will find yourself stuck in stop and go traffic almost on a daily basis. But people in LA love their cars! So don't worry! They roll down the windows, listen to loud music, or NPR (there’s a fabulous public radio station that’s famous nation wide called KCRW!!) -- and so don’t get nervous about all this driving. It’s part of the LA experience! Throw on your shades, pop your windows, blast your favorite tunes, and drive like a mad person to your audition knowing you’re gonna book the job! It’s fun!
That being said, it’s really important to have a safe car to get you around. Make sure you change your oil every 3,000 miles. Make sure you have good tires on your car that aren’t low, bald, or misaligned. And you might also want to get a car that gets good gas mileage. I have friends that drive over 300 miles a day in LA. They try to save rent money by living way up north in the valley, and then they drive in to jobs waiting tables in Hollywood, where they also go on auditions every day. This same person drives an old SUV, which gets terrible gas mileage. And with the prices of LA gas ranging between $3.80 and $4.50 these days, driving a gas guzzler just isn’t worth the money!
One other thing to remember. At most acting auditions or rehearsals, jobs, or even bars or restaurants in LA, there will only be street parking. So you might not want to arrive in the city driving a really hot expensive car. You will find yourself parking in back alleyways, and along crowded city streets -- and a brand new Mercedes or old cute convertible might get broken into: one more reason a compact car is useful. It's easier to park. Also realize that most casting offices do not let you park in their lots. You are constantly driving around the block looking for a meter, or some dirty parking lot to park in, and you usually have to walk several blocks back to your audition. Keep this in mind if you're buying a new car before you move to LA. Think "utility" not "flash".
Like most LA actors, your car will be your home away from home, so make sure your car is in great working condition, and is reliable, and fuel efficient. Put your pedal to the metal and go! go! go!