It seems to me that almost any 1960-1985 Heuer in excellent shape is at least a $1200-$1800 piece. I'm not sure how the $1800 is significant as a floor. Perhaps the best way to go would be to adopt the numismatic convention: nos/mint/excellent/vg (probably not worth going deeper than this because with pieces that require attention you cannot reasonably estimate restoration and repair.

I think it is important to include the "lesser" models, especially in light of the fact that the Monacos and brand-name Autavias have jumped out of the reach of many collectors. For some models (Kentucky, Verona) the SPY will oviously be small, but for, say, Calculators, there is enough velocity to get an accurate picture of value.

with the price of original straps and bracelets so high, I think it would be helpful to note the impact on value. It seems more and more that watches are trading as "head only."
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