Wanna get Halloween Costumes for free? then enroll friends, neighbors and family in a costume swap party. Chances are that you have friends and family that have outgrown Halloween costumes they can no longer use. But maybe you have some that they CAN. So get together as many friends as you can and swap those outgrown costumes with each other. You don’t even have to give the costumes away. Most costumes are only used for hours so you can lend costumes to each other.