In a toilet bowl composed of a plurality of resin-made components, at least one resin-made component includes a base material made of a foam synthetic resin, and a coating layer made of a polyurea resin covering a surface of the base material. A flush toilet tank includes a base material made of a foam synthetic resin molded in a tank shape, and a coating layer made of a polyurea resin covering a surface of the base material on an inner surface and an outer surface in the tank shape. A pipe body inserted, as a new pipe, into an aging already-existing pipe includes a base material made of a foam synthetic resin formed in a pipe shape, and a coating layer made of a polyurea resin covering a surface of the base material on an inner surface and an outer surface in the pipe shape.