Time for beloved collection to find new home(s)

My daughters, identical twins, created their own twin-world Playmobil world throughout the 1990’s. Every figure was part of a family. Each figure and family had its own backstory, personality, and quirks. Storylines were ongoing, creating a history of Playmobil world and its inhabitants. There must be 20 or more sets in the collection. We lost one daughter when they were 17. It is very difficult for my surviving daughter and myself to think of letting go of the Playmobils that formed this shared world. However, it is time we must. I read on an old r/Playmobil post that selling Playmobils to collectors is the best way to ensure they are taken care of. My problem is that the pure white parts of these toys have yellowed to a deep tan. I have tried using peroxide in both liquid form and developer form. This will lighten them some, but just to a lighter tan. I don’t know if anyone would want 1990’s Playmobils that have this aging issue. My daughters were exceptionally particular about caring for all of their belongings—and especially so with their beloved Playmobils. They are in like-new condition, aside from the aging on white parts, and still have boxes. Thoughts?