Wow! And I thought you had 2,000 for all three of you. With 2,000 each, you should be able to live like lords of the manor (well, maybe not quite).
Definitely set up an account here. That will save on international charges for ATM use. Also make sure it is with a bank that has a countrywide distribution system, such as Bank of America. If not, you will find that even local ATM charges will soon be making a hole in your budget.
If there are three of you, you may actually find it is less expensive to rent a car in California. For example the Los Angeles to San Francisco fare is US$ 48.00 each. You can rent a car in California for a week at that price. You should also keep in mind that renting a car in one state, and dropping it off in another may involve a hefty drop-off charge.
http://www.greyhound.com/
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