Ottawan,
I am not all that old, but not a youngster anymore, either. I have thought about that from a slightly different perspective. I still don't have enough documentation of what I have and where it is. I know it all, and have the records, but they are not ready for someone else to use. I made progress this year, but it would still be a real detective job for someone to figure it all out. And, then, there is the website, Figs 4 Fun. Who would take it over, and maintain it? Who would add to it and improve it? I am sure I am prejudiced, but I think it would be a shame to see it disappear.
My wife would not be able to keep up with all of the plants, and the kids wouldn't want the plants, so they would need new homes. How do you figure that all out? set up a donation to UC Davis, or some other collection? How do you get them there? Turn the property into a botanical garden or foundation? Where does that money come from?
That is part of why it is so important to duplicate things in various places - trading cuttings and such - to share.
Hope someone has some wisdom on this subject.