Walmart offers the Mainstays Twin-Over-Twin Wooden Bunk Beds in four colors (Walnut pictured), model no. WM3921, for $179.88 with free shipping. That's tied with our mention from ten days ago and $77 under the lowest total price we could find for similar set elsewhere. These beds can also be used unstacked. They feature a wood slat system intended for coil-spring mattresses.