My child wanted to be a Transformer that transformed. After doing a lot of research and trying different ideas we came up with this Bumblebee Transformer Halloween Costume.
We used this idea, because of how young our son is; we did not want anything attached to his arms. We took a box that fitted the child, with the top of the box open. We cut off the 2 side flaps and then down the side of the box; that would be the underneath of the car. So the box should lay flat with 4 sides. Take an old backpack and taped it to the inside of the box for the straps. Make the top of the car with another box and attached it with tape; that will get it the 3-D look and be the windows of the car.
With one of the flaps you cut off; re-attach it to the front of the box at a 90 degree angle. Cover the bottom with black felt to hide the back pack. Cover the top with yellow felt and glue the details.
For his clothing we purchased the costume for him to wear; it comes with a mask as well.