Many people rent a room when they are young. The problems are obvious: lack of privacy; not enuf room in the refrigerator; lack of adequate parking. But the cost of a studio apartment in the safe parts of LA is $1,000. Very small..... 400 sq ft. You can rent a room in LA for $500.
The LA area has 8 great websites for finding rentals; but only Craigslist has the roommate offerings. In some apartment complexes, the bulletin board next to the mailbox will have rooms for rent. Don't forget to check out mobile home communities, too.