I find it interesting that collectors of various sorts seem to be split on whether restoration is desirable or not. Certain collecting hobbies value originality above all else, and a piece restored in any way would be considered worth less than the same piece in original, unrestored condition. Sometimes certain limited types of restoration or conservation are allowed while either helping or at least not hurting the value of the piece, and other times, a restored piece can be worth more than one in an original but damaged condition.

How does it work with rare books?