Cheap Bed

Base textures obtained from cgtextures.com

Make 'Bed' object (or make a child archetype) with the following properties;
Shape > Model Name: CheapBedRS

Physics > Model > Dimensions:
Offset: X: 0, Y: 0, Z: -0.7
Size: X: 3.99, Y: 7.24, Z:1.6
(these settings give you a phys model whose top lines up with the matress, 
rather than the bounding box of the object).

R Soul