What comes after the Coroplast?
 

Coroplast is a cheap mock-up material, but once you have finalized a design what are the choices for a more durable material? Comes now Trusscore
It's Been a Good Run, Drywall.
Similar to Coroplast but made from PVC with non-perpendicular webbing, and baseball proof. Available in sheet 12ft long and longer. Maybe not suitable for wheel spats or Kammbacks. but as a belllypan it should work well.