Here is a car we all need to be careful about. Fred has done the tedious work of cutting out the sides of this high sides gondola to convert it into a hopper. Marx collectors recognize the possibility that legitimate examples of this car might be floating around but, as yet, none have surfaced.
This one demonstrates that you have to be very careful if you find one. If it's cheap it's might be legit. If someone wants a bundle of money for one, be extremely skeptical.

(Courtesy of Fred Pauling)