Twin Beds with Trundle DIY.
Determine the amount of boxes you want. Screw them on the middle piece. Screw the lower piece of MDF on the frame with an electric screwdriver.

Twin Beds With Trundle Black

Twin Beds With Trundle Brown

Twin Beds With Trundle Low

Twin Beds With Trundle Metal

Twin Beds With Trundle Nice

Twin Beds With Trundle Set

Twin Beds With Trundle Storage

Twin Beds With Trundle Yellow