I'm not an expert, but I've never seen a #3050 coach in blue. The colors I know of are green (3rd class #3050/30500 - most common version), green/brown (3rd/4th class mixed #30503), brown (4th class #30504), or red (a Christmas version #31500). I've never actually seen the Christmas one, but it appeared in LGB's catalog.
There was a blue version of the postal wagon produced in the 1980's as part of the anniversary series (1985 Jahreswagen) but I believe the original 3020s were all green. The later versions were also produced in green (most comon version, #3019/32190), brown (most sought after- actually a baggage car labelled "Stuckgut" #31190) and an absolutely wierd red and gold Christmas version (#34190), complete with a huge ribbon and bow. These all had interior furnishings and lighting and end marker lighting; some also came with ball bearing wheel sets. I have one of each of these (SWMBO bought the Christmas one for me).
In addition, I think it has generally been LGB's practise to mold the bodies in colored plastics as much as practical rather than paint them (unless of course it was a multicolor scheme). So I would suspect any car that was painted in entirety as not being original.
BTW, there's one of the early 3020s currently on eBay listed at $300.
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of this glorious country that official utterances are invariably
regarded as unanswerable."
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