Probably a poor data point, but I paid $8,500 for an RV-4 project in 2006. Probably a kit from the 1990's.
Only major parts missing were wheel-brake assemblies.
Oh, and two of the wing spar plates were missing. That reduced it from the asking price. I had to do some precision machining to re-make them from blanks. Of course, also ordered a number of nuts/bolts/washers/rivers/pop-rivets, spinner bulkhead and so on.
But probably better to compare to price of new emphenage and wing kit. Take into consideration workmanship and any missing pieces and hardware. Also any corrosion will be a factor.
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