I built my own using 2x's and plywood for the frame, and 1x material for the drawers. So far so good. It wasn't difficult, took a weekend to assemble and a few days sealing the wood. I used automotive carpet to cover the box. I toyed around with using drawer slides but couldn't find 6'-8' drawer slides that I felt would hold the weight of ammo, guns, etc. So I went without them and it is working fine. My only recommendation is to drill holes in the rear (near the cab) of the box to allow air to escape, makes it a lot easier to open and close the drawers. All told I spent about $150-$175 in material (this was before the price of plywood skyrocketed!), a considerable savings when compared to Truck Vault.