offhand, I'd say if it's got true temper tubing (likely on a 400), talk him down. Half that is reasonable, unless the bike is in excellent condition or overdressed component-wise. The Ishiwata is very nice stuff, but undervalued, where Columbus and Reynolds somewhat inflate the bike's value.
"All you out there in the world of the real bike economy can have the benefit of know-nothings selling their bikes in less competitive markets."
Heh-heh-heh. That's what you get living in an overheated market. I've said this before, but I am constantly surprised at the incredible geographic variation in used bike prices. The pre-84 Treks are special, but the 400 model is likely mid-late eighties.
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