You're either going to love or hate this idea, but...
If you're short of storage space or you're having a clear-out, have you ever considered taking digital photos of items that have nostalgic or sentimental value for you? The photo will still evoke the memories but will take up much less space than the original item.
For other tips to help you get and stay organized, visit Unclutterer.com. There's a useful section there about dealing with inherited clutter - 'objects that legally come into
your possession or responsibility after the loss of a loved one or when
a family member is transitioned into a retirement community or nursing
home'.