Yes, you are permitted to leave the Toy Story Parking Area and return later that same day without paying a second time. When you first enter and pay for parking, the attendant will provide you with a paper receipt. It is crucial that you keep this receipt, as you will need to present it at the toll booth upon your return to prove you have already paid for the day. This policy is particularly helpful for guests who want to return to their hotel for a mid-day nap, a swim, or to change clothes before the evening fireworks. Once you re-enter, you may not be able to park in the exact same spot, but you will be directed to an available space. Using the "Car Locator" feature in the Disneyland app is recommended so you can easily find your vehicle's new location after returning from the parks.