any suggestions for rental car agencies, routes and hotels would also be helpful. thanks
1. Guy G
According to CostToDrive.com the cost for driving from Oakland to LA (using a typical car, say a 2006 Chevrolet Impala, would cost you $55.86 one-way ($110 round trip) using today's gas prices.
You may find a cheaper alternative is to buy a package from a site like lastminute.com as you are traveling over a weekend and are within 2 weeks of your departure date.
2. Still Standing
It depends on the dates (weekday or weekend), how long you will have the rental and what places you are planning to visit in LA.
For an economy rental car at Enterprise, just for 4 days it can cost you around $160 with taxes and fees, then for a hotel in LA such as the Hilton near LAX is around $750 for 4 nights.
If you combine a FLIGHT, staying at the Custom Hotel and rent a full size Hertz car for a total package (to make it easier instead of paying for traveling gas from Oakland to LA), it can come up to $750-800 for everything excluding gas for commute to wherever you need to go in LA and restaurants/tips, etc.
Hope I helped :-)
3. Cheese N
for car rental you can get a coupon code from rentalcarscode.com