Need to find a value for a  1983Mercedes 280 GE. Blue books don't go
back that far, or I can't find one that does.

Hello,

According to NADA Guides, a two-door 1983 280 GE would go anywhere
from $3,975 for "mechanically functional, needing only minor
reconditioning;" to $9,250 for "good condition;" to $14,050 for
"excellent condition."

A four-door would run $4,575, $10,750 and $14,600 for the three
categories above, respectively.

To reproduce these results, go to (www.nadaguides.com), click on
"Classic Cars" and then on "What is your classic car worth?"

I hope this answer meets your needs. If not, please request clarification.

Search strategy:

used car value
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