The largest collection of Märklin wagons belongs to Gilles Monk (Belgium), with 1982 different pieces, which he has been collecting since 1980.

See Märklin history attachment. CD with pictures of all trains provided.
Mr Monk’s favourite train is the “Crocodile” which is an entirely gold plated train produced in only 50 pieces for a press conference held by Märklin in 1983, only given to journalists.