Wayne,
In what sense do you meaan "most value?" Monetary? or Importance?
I believe that there are some that the owners of have no idea as to their importance. For example, take Tilly's drawings, prints, sketches, etc... All of Tilly's own work, documents, prints and sketches, correspdondence photographic negatives, etc... were destroyed in a fire that destroyed the barn where they were stored after his death on his son-in-law's property.
As a result, anything of his, especially in his own hand, takes on a greater value both monetarily and historically.
Too many clubhouses have burnt down or documents lost for the single reason of 'cleaning out the closet' and these precious items are lost for all time. That is why it is imperative that clubs cooperate with the USGA's effort to compile course evolution histories...