I designed this hanging lantern to snap together. The wall snaps to the base and the ceiling snaps to the wall. The wall covers slide in between the walls.

Each part has a built in 0.2mm gap to make sure that things aren't tight and can snap together relatively easily. You may still have to apply some force but as long as you are careful, the pieces won't break.

I found that flipping the base 180 degrees in your slicer s the best for printing. Additionally, I found that grid supports for the wall was the best support kind. I used Cura and prevented the slicer from generating supports past the snaps at the bottom of the wall.