Provided is an apparatus comprising a tray assembly and a wedge rod assembly. The tray assembly includes a roughly-cylindrical paint well, tool orifices, and a handle for one-handed carrying, adjusting, and moving the tray. A button is provided on the handle to allow detachment of the tray from a ladder without the need for two handed operation. A locking or wedge rod assembly is provided for securely interfacing the tray assembly to a hollow-rung ladder. By rotating a grip on the wedge rod assembly, a top platform on the wedge rod assembly extends vertically to engage the interior surfaces of a rung of the ladder, and thereby locks the wedge rod into place. The tray assembly may then be adjusted to the desired angle and attached to the locked wedge rod assembly by engaging the coupling areas. Depressing a button on the handle of the tray assembly releases the tray from the wedge rod assembly and ladder.