Airstream (Oscar) Rental
The Airstream holds a maximum of 6 people. The $30 charge is a non-refundable deposit that covers one hour in the Airstream and will be added to a tab to contribute to paying for your food, drinks, merchandise, etc. (from Mountain Cowboy) once you arrive. As stated above, the deposit is non-refundable and will not be paid back if you do not spend it all on food, drinks, merchandise, etc. here.
If you would like to be guaranteed more than 1 hour in the Airstream, you can book multiple slots and the deposits will still be used to contribute to your tab. If you'd like to stay past your booking time but don't want to put down a deposit, you can take your chances, but be aware that if someone else has booked the Airstream for that time with a deposit, you will have to leave.