Hi all,
I'm currently an undergrad at USC, and will be headed off to Boston for my PhD in a few months. But I'm happy to share my knowledge.
PhDerp - regarding the second car - at most apartment complexes you can definitely purchase a second space, but they get really pricey. A space in a gated apartment complex usually runs about $200 a month. You can typically purchase a tandem spot that has room for 2 cars for about $300 a month in most buildings. However, there is also A LOT of street parking in Los Angeles. I have never paid for a parking spot for my car. Most of the streets around campus have open street parking (except for Tuesdays from 8-11 am when they do street cleaning). So as long as you can remember to move your car every week at that time, you've got a spot for free!
jzhu - There aren't many trails around campus. Most people choose to run on the campus itself (the loop around campus is about 2 miles). Staying within the gates keeps you safe, and the campus is the best place to run for a nice view. Also, anywhere north of campus is safe to run. A lot of people will run the blocks around fraternity row, and even up to downtown LA. Basically the rule for going anywhere alone off campus is to stick East of Vermont Ave., West of Grand Ave., and North of MLK Blvd. This hold for any time of day.