Updated 31.05.2014

Single cars means that they come one by one in separate boxes with individual article numbers.
The lists is sorted by the Märklin article number.
More will be added step by step.

Cars with lower than 44-series item numbers:

 First Märklin 00767, "Red Marker Lights" Display with 12 Freight Cars.

00767Limited special models in 2012.from a dealer display set with 12 freight cars.

• Available individually at your authorized dealer in a well-arranged display.
• All the 00676 cars have a oick-up shoe and rear red lights.  No rear coupler.
• it was 4 type lbdlps 383 (former Tnfhs 38) refrigerator cars in neutral paint and lettering schemes, 4 type lbdlps 383 refrigerator cars painted and lettered for the Baden State Brewery Rothaus AG. 4 type Eaos gondolas with coal load inserts. All of the cars look as they did around 1979.
   All the cars have factory-installed red LED marker lights. Centre conductor pickup shoes provide power pickup.  The cars have no rear couplers. All the cars have different car numbers. and  comes individually packed in marked boxes.  I have one of each car type.
  

Märklin 00767-04, DB LIbdlps 383 802 4 753-9

L = 13,9cm.  Limited special model in 2012.from a dealer display set with 12 freight cars.

• Available individually at your authorized dealer in a well-arranged display.
• All the 00676 cars have a oick-up shoe and rear red lights.  No rear coupler.
• Märklin 00767-07, B LIbdlps 383 082 5 609-9
  
  L = 13,9 cm.

   Limited special model in 2012.from a dealer display set with 12 freight cars.

  • Available individually at your authorized dealer in a well-arranged display.
  • All the 00676 cars havve a oick-up shoe and rear red lights.  No rear coupler.
  • 
    Märklin 00767-12, DBEaos 421 2 157-4
    

L = 16,1 cm.

 Limited special model in 2012.from a dealer display set with 12 freight cars.

• Available individually at your authorized dealer in a well-arranged display.
• All the 00676 cars havve a oick-up shoe and rear red lights.  No rear coupler.

Märklin 31636, DRG  refrigerated freight car set Hengstenberg

I do not know why his set, produced in 1995, has a number in the 31xxx series.

Märklin 34900, DRG G10. 517 661

L = 11 cm, Limited special model for model railway shops in Germany  1995 <>(Limitiertes Sondermodell 1995 - für Modellbahn-Fachhändler in Deutschland).
Mine was bought in Oslo in 2000.
I do not know why this car has a 31-series number.  31-series is normally for locomotives. I thought that this might be a advertising car or something, nut it is listed as 34900 in Märklin Archiv, as all the other official Märklin models.

I would say that this car should belong in the 46-series or higher.