If you ever do find yourself contemplating that sort of money, then I would recommend Purple Parking. But not the drive-out-to-them-and-have-them-bus-you-in service. They do a meet-and-greet - you drive to the front door of the terminal and they take the car off you. When you get off the aircraft when you return, you phone them. All being well, shortly before or after you get out of the front door of the terminal, the car will be there. Just priced it for 5 calendar days plus meet-and-greet: £85.

If the NCP want that and you still have to get a shuttle bus to and from the carpark, they're poor value in comparison.