What were the four Walthers pass car types produced? No diner or duplex that I know of.
10-6 PS plan 4140 (smoothside) and 4140A (fluted).
Coach- 64 seat NYC prototype produced in both smoothside and fluted (I think this is prototypically correct, some of the fluted cars had their fluting removed in later years).
Baggage- 70' (inside dim) full baggage from Chicago Great Western prototype. Produced smoothside (prototypically accurate), 1/2 fluted (to go with C&O cars) and fluted. AFAIK, the 1/2 fluted and full fluted are foobies.
All the cars were produced in both accurate and foobie paint schemes.
I don't recall there being a 4th body style, but memory is not my strong suit nowadays.