Probably would cost $60-$80 but could be higher if there's a lot of traffic (fees are based on both mileage and travel time). Worst traffic times are 7:00 am to 9:30 am and 3:30 pm to 8:00 pm.

Sunset is fine, keep the passengers on the curbside is a good way to remember things when you are driving. When you get to Santa Monica switch to Wilshire Blvd. Stop at El Cholo grab a bite to eat and then keep going down Wilshire to Ocean Blvd. Stop and watch the sunset, you can park here and sit on the bench. It's beautiful. If earlier, keep on Sunset, as you get near the coast, keep an eye on your left and when you see the Self-realization fellowship pull in and take a break walking around the gardens. A little hidden treasure, then back on Sunset to the PCH (Pacific Coast Highway) turn right and you are on your way to Malibu my friend. If you like to pack your schedule, call the Getty museum and see if you can get in that day. You will be going to the original Getty museum which has been renovated and worth your time seeing. Have fun, stay safe.