The listing does state 3 film holders - but these cameras came with plate holders, not film holders. The plate holders can be used as film holders with film inserts, which the listing doesn't mention at all.
I have one marginally usable RADA (for 6.5x9) and one junk (for 9x12).
I also happen to have three 9x12 plate cameras (Rodenstock, Voigtländer Bergheil and Avus) and three 6.5x9cm (Voigtländer Bergheil and VAG, KW Patent Etui). The Bergheils are clearly the best cameras, but they are also clearly the most expensive ones. Especially with Heliar lenses in rim-set shutters---