$12.00 Bag that can be stowed in luggage on the way there and filled with souvenirs on the trip.

 $34.00 Bag. 21.85x15.7x12 maximum size carry-on. This bag will be in overhead on the way to Europe then checked on the way home because the above bag filled with souvenirs and your backpack become your carry-ons.

Here's another packing video (for girls)

Packing video