A storage cabinet assembly for use in storing firearms or the like includes a cabinet with a recessed bifold door arrangement, to facilitate access to items contained within the cabinet assembly. The door arrangement includes a single-point locking system, which provides a secure arrangement for maintaining the doors in a closed position while providing ease in opening and closing the doors. Various support and storage modules or components are adapted to be contained within the interior of the cabinet, including stock rests for positioning in the bottom of the cabinet interior, as well as barrel rests and pistol supports that are secured to amounting member which may be adjustably positioned within the storage cabinet interior. A bin or shelf arrangement may also be positioned within the storage cabinet interior. The various support and storage modules or components may be used in various combinations, and may be moved to various positions within the storage cabinet interior.