Rusty has shown the "classic" image of a mixed train out of Beebe and Clegg's "Mixed
Train Daily", however most of these are never shown with that many passenger or
freight cars. I would definitely think six coaches would rate their own train. The
Great Western used to run long freights of sugar beet gondolas with a combine
coach (now displayed at the Colorado RR Museum in Golden) on the end. Some
of these ran with one car, a combine RPO/baggage/coach on the end, and whatever
freight cars needed to be moved. Sometimes, in switching, the combine wound
up elsewhere in the train, on these branch and short lines.
The Louisville and Nashville, ran a Jim Crow combine (baggage door in the middle
dividing two passenger compartments) on the end of its mixed run through my great aunt's farm in Shelby County, Kentucky That was hauled by a diesel road switcher in its last years.
Definitely my favorite type of consist.