Possible Clues:

• It's on the house for those who are tortured carrying baggage from place to place
• Carrying lots of baggage for The Tourists on the house and one of The Frames
• Over-the-top luggage holder?
• How bikes go by car
• OK for car to have this re-fitted?
• Luggage holder, often
• Car OK for trips? Car accessory needed
• Attachment on car
• Attachment to car
• Bags I get on this fine estate, say, erected inside castle