They sell for $250 to $300 in Chicago. The Record seat post and FD can add a bit of value but only if he is including the original pieces as well so you can sell off the Record pieces and extra saddle. If the bike is in great shape as listed, not the worst price. If it needs all new consumables not very good at all. You can get them cheaper but they may take some work. If you good with a wrench, cheaper can be good, if not......
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My bikes: 1970`s Roberts - 1981 Miyata 912 - 1980`s Ocshner (Chrome) - 1987 Schwinn Circuit - 1987 Schwinn Prologue - 1992 Schwinn Crosspoint - 1999 Schwinn Circuit - 2014 Cannondale Super Six EVO