Sofa sleepers are always tricky to design. Unless you have history with your fabricator & have the component sizing defined with a proven track record for what works, its a risk to manufacturer a large quantity. How about this design! The seat cushions “lip” both the front & back and lined with a black grip fabric so it doesn’t slide. The back cushions have the same fabric but only on the bottom to help keep cushions from slumping. Great solution for hotels & vacation ownership properties!