I have two buildings on my layout from my childhood layout. My father scratch built them in 1950 for our Marx Christmas layout that came back each Christmas. He made them from 1/8 inch Masonite and packing board and used brick and roofing paper on the exterior. He used a pedal powered jigsaw to cut the pieces and cut out the doors and window openings. My brother still has the saw although it has a 1/4 hp motor now.
Post some pictures of or from your childhood layout so we all can enjoy them.
Charlie