I dismantled the door to replace the latch so I decided to add insulation, paint the inner panels, and prepare it for some custom upholstery. I bought the reflective insulation at Lowes and chose gray as the color for the panel. I bought Plasti Dip paint as it's a rubberized paint and is supposed to adhere better to the plastic.
A fresh coat of gray Plasti Dip rubberized paint.
Kathy working on the insulation and material for the door. We purchased the material from Hobby Lobby, and used Gorilla Glue spray adhesive to attach it.
So we went from this to this! We have around $20 in materials for our custom door. We are proud of our project, not bad for amateurs.