With the car in bare metal, it's best to go to the paint shop for prepping and priming within 24 hours, not just transported and parked inside the body shop within 24 hours. Make sure you coordinate this schedule with both shops before the car is blasted. You'll also want to keep track of your local weather forecast (and your work schedule) to make sure your car is not caught in a downpour on the way to the body shop. If you contract the transportation part out, be certain to be along for the trip and make sure no one touches the fresh metal--especially with greasy hands. Remember, rust loves bare metal, especially when it's humid, cold, or rainy. Don't rely on your good luck.