In 2012 I researched TÜV approved rock & roll sofa beds for my conversion but with shipping from Europe $2.5-4K total cost led me to my own design. I designed and built my own for the Sprinter conversion using aluminum frame. At the beginning of the design phase I was contemplating 3 versus 4 panel designs ultimately settled on 3 panels. My key reason for this decision was better space with 3 panels design, the front panel moves back full 3’ from bed to seat positions.
So, why did you choose 4 panel design?
Which NA standard did you use to get legal approval for safety?
Does your >$5K price includes floor guides?