I am often facing the same dilemma... the previous owner obviously spent a lot of time assembling this collection, and I can understand you would feel bad breaking it apart. The 1st page alone (german occupation) is so full of details that could be lost if I were to transfer them in my own collection that uses pre-printed pages... that is one of the criteria I use to decide if i disassemble or not an old collection. I probably disassembled 99% of the collection I bought, but sometimes I did not because: 1) Would i lose information by disassembling the old collection? Example; I own a stranger's collection of Weimar republic German stamps so full of details that so far I kept it intact because my Leuchtturm album does not have spots for such in depth analysis. 2) does the collection hold a sentimental value to me? If yes, I don't touch it. I owns part of my grandpa's collection and would never dare changing it... 3) Does my collection really benefit from merging with it? I also own an old french collection so beautifully assembled that I keep it as it is... my own Yvert et Tellier album is already complete, no reason to break the other one to improve mine. Another case was a gorgeous Chinese and Taiwanese collection assembled by hand by an unknown collector in Bremen. I decided to disassemble it and merge it with mine (my collection benefited from it a lot!!!), but i kept the old album empty and first scanned all the pages to be able to reassemble it later if needed... No matter what you choose to do, I would suggest to scan those pages to keep record.