My solution to underbed storage
I built in a large drawer. I used the ball bearing sliders from Home Despot. They have nice feel, but are kind of heavy.... This drawer finished up the wood I had left over from the shelves, cabinet fronts, and front dinette I built. I ended up having to use some of the pine from the bunk bed for the sides. Kind of mish mash of wood on the inside, but it looks great closed.