This article is from the Woodworking FAQ Collection 1, by multiple authors.
A question easier to ask than answer. This varies greatly
depending on condition of the tool, and the geographic location.
As a ROUGH guideline figure about 60-100% of current retail if
it's a plane Stanley still produces and its in good shape.
It also depends who you are. For example, a #7 jointer plane
sells retail new, for anywhere from $65 to over $110 dollars.
Tool dealers ask from $75 to $100 for them. If you live in the
right area, you can often find them at flea markets, antique
malls and yard sales for below $30.
In general, if you are new to the purchase of old tools, avoid
buying things that cost much more than $XX (insert however much
you're willing to blow on worthless junk) without acquainting
yourself with the going price. Do this by talking to tool
dealers (see the handtool faq for a list of folks on the net) or
consulting price guides. Local dealers of tools in antique malls
often way overprice their tools. But then again, they
occasionally underprice out of ignorance.
 
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