NADA is a joke, and is used by Auto dealers for value of cars for 'trade in' value which we all know is shit. KBB is a joke as well. I use Hagerty which uses Auction Prices and Insurance Value Trends, which both of these tend to reflect the direction of a market for a car much more accurately than dealer values that kbb and nada use. So with that, below is a value graph from Hagerty for an 86 GN....
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