Abstract: A method of stocking a building under construction with wallboard panels, and apparatus. A stack of horizontal panels is delivered to the building site by truck, and removed by a fork lift truck, and then placed on a pallet provided with transverse rollers. The pallet, loaded with the stack of horizontal panels, is lifted to an upper floor, and a self-propelled transporter vehicle on that floor is placed adjacent the pallet. The stack is transferred as a unit to the transporter, which then delivers the stack to a desired location on the floor of the building, the stack of horizontal panels being discharged as a unit from the transporter.The pallet has three sets of rollers, longitudinally spaced, so as to provide between each two sets a passage which is upwardly facing, unobstructed, and which will receive one of the tines of a fork lift truck. One of the rollers is powered from a source of energy carried on the pallet.