Question for you regarding UPSP Priority flat rate boxes and envelopes for international use. Once I put the customs documents on the box / envelope should I also print the return and sender address on a separate piece of paper or label and put them on there? If so where should I place them? If I put the customs form in their clear envelope on the top of the flat rate box or one side of the flat rate envelope there isn’t much, if any, room for addresses directly on the box or envelope.

Thanks for your input!