The Century Blvd location is off the 405, you can either go North on the 405 from the 105 or take Aviation as was mentioned. You can get a ticket from the machine when you first arrive and use that to checkout, but you'll need a credit card (I believe they also have a cashier window by the Valet on the first level if you need to pay cash, but not at the exit). If you book a reservation online they should give you a QR code to scan that will work as well
I take the 105 and exit Aviation. Turn left off of fwy then the first right is Aviation. Take Aviation to Century and turn left. The Parking spot will be on your right.
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