A base assembly of a prefabricated wall system includes a base extrusion, a base track, and a leveling assembly. The base extrusion includes an upper channel that is at least partially defined by first and second vertical members, and the upper channel is configured to receive an edge of a prefabricated wall panel. The base extrusion includes a lower channel opposite to the upper channel. An opening of the upper channel and an opening of the lower channel are oriented in opposite directions. The base track comprises a base track channel configured to affix to a floor of a building. The leveling assembly is configured to reside within both the lower channel of the base extrusion and the base track channel of the base track. The leveling assembly is adjustable to adjust a vertical position of the base extrusion with respect to the base track.