There is an active forum right now about the worth/interest in K-Line 18 and 21 inch aluminum passenger cars. I have similar thoughts about other K Line cars-like the 641-series box cars, the 632-series die cast chassis tank cars. I am an old Lionel boxcar nut-and treasure my collection of PW 6464s. But, to be honest, the 6464 type box cars made by Lionel after 1969 ( especially recently) are (too) expensive-and the almost exact K Line cars of the 1990s and early 2000s were less expensive and, in fact, more detailed with some interesting road names. The same for the very nice die cast chasis K Line single/ triple dome tank cars. I know their worth will likely never increase-but they are fun, IMHO, to collect. Most are still readily available-but there are some, especially those made for clubs or in sets, that are hard to find.
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