Systems such as the 3DO, Atari 2600, 5200, 7800, among others have variations that pull a different value than others in the line. Example: An Atari VCS (2600) Sunnyvale Heavy Sixer pulls a bigger price tag in comparison to a Light Sixer, or even a "Vader" (All black model). Even Atari 2600 Jr.s have a different value in comparison to the other versions. Sometimes, it is also due to hardware changes. Example: The Atari 7800 has three revisions. The first release version has an I|O port for connecting to a Laser Disk player (Never supported), and later versions removed the port, to completely removing the cutout in the chassis.
Newer systems in the listing seem to support this, however, I also understand that this has a LOT to do with the sellers knowing what they are selling to be able to differentiate between variations. As long as we can get "something" to help create a bit more solid listing on vintage consoles, it would greatly help in establishing accurate valuations.
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