A gutter piece and a method of forming the gutter piece including the steps of: obtaining a gutter forming apparatus with a marking subassembly; obtaining a supply of gutter material; through the gutter forming apparatus, progressively forming the gutter material into completed gutter pieces, each with a length, as the gutter material is advanced in a forming path; and through the subassembly, continuously making discrete visible marks on the gutter material as the gutter material is advanced that: a) reside at predetermined intervals along a length of each of the completed gutter pieces, and b) are located to facilitate controlled interval placement of hangers that are used to support the completed gutter pieces in an operative position on a structure.