David Soderblom writes:

Richard is (as usual) correct about the engineering of the cars (i.e.,
the multiplicity of combinations of ends, roofs, etc.). But the
essential point I was trying to make (not very well) is that modelers
don't buy kits because of the prototype populations but instead because
they want the car in question. That statement holds true for the
members of this list as well, otherwise Martin's kits of truly obscure
prototypes would never sell. I will wager that the numbers of X29 kits
sold by Red Caboose are proportionately smaller than their prototype
population compared to, say, the GS gons they brought out, and that has
to be certainly true in comparison to the F-70-7. Therefore talking
about the prototype population as though that drove model production is
misleading.

True, David, but only up to a point. Citing Martin's "kits of truly
obscure prototypes" muddies the water because tooling costs for resin kits
are trivial by comparison with tooling costs for injection molded plastic.
Ask Martin or Al Westerfield about production numbers and you'll find that
a resin kit for which sales are a thousand or more is a runaway success; in
many cases the number is more like a hundred or less (sometimes far less).
What makes choosing prototypes for styrene models a crap shoot is that such
large numbers have to be sold before you recover your tooling costs, so you
may not actually begin to make a profit on a particular model for months or
years (if you ever do). And as the obvious prototypes which can be painted
and lettered for a gazillion different owners (e.g., AAR and PS-1 box cars,
Greenville gons, Type 21 tank cars) get used up, choosing prototypes to
model gets more and more chancy. Will a really good styrene model of a B&O
wagon-top box car sell enough copies to even pay for the tooling? Nobody
knows, though sooner or later we'll probably find out - and the news may
not be good. With regard to the 1932 ARA box cars, both Bill Schneider and
Marth McGuirk have now weighed in on the list with admirable candor.
Making such decisions is how these guys earn a (perhaps somewhat
precarious) living. Anyone who wants to second-guess them deserves an
award for valor. If you want to make a small fortune producing styrene
models of 1932 ARA box cars, make sure you have a very large fortune to
start with - and if a sizeable tax loss would be to your advantage, so much
the better.

Richard H. Hendrickson
Ashland, Oregon 97520