Yeah--a big "YES!" to reflectors. They can be made of many things...wood, steel, aluminum sheet, fabric stretched on metal, wood,l or PVC pipe frames, pizza boxes, styrofoam board sheets like disposable styrofoam cooler lids or industrial styrofoam sheets or squares, home insulation board, "poster board" or "foam-core board"...almost anything....even white bedsheet material on PVC framing.
Styrofoam boards, kind of thick ones, like 1 inch thick, are really light, but strong, and are good for smaller reflectors. I like 42 x 78 in ch reflectors, with white fabric, on high-grade PVC frames. Why? TWO of them can be clipped, or lashed together, and a tall, free-standing thing called a V-flat can be made...the overhead view is like that of a letter "V", and the from the back or front, it looks like a tall, slender book, opened up and placed standing upright. THis can be used to bounce light back, toward the subject and/or the background.
Reflectors are a ************huge************ part of controlled, studio lighting. But they do not necessarily have to be large, or factory-made.