First, please define "old Construction Drawings". I will assume that you mean new prints of old projects. Many times I've been contacted by Owners of buildings designed by my firm, which was founded in 1935. I am happy to talk with them, tell them that I'll research what is in our Archives, & sell them prints for their use. Sometimes they say no thanks, some buy prints & go their way, & some have hired me to do an addition &/or renovation. The "value", or selling price, is a "market rate" decision, & depends on the size of the original project. I usually try to at least cover my time, my assistant's time, my printing costs & add in some profit.
Second, NEVER SELL YOUR TRACINGS!
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Carl Handman AIA
Owner
Eyerman, Csala, Hapeman & Handman
Wilkes Barre PA
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