What to do with a 25K pc collection?
Since no one answered here, I will post an update on what I have done so far. I will update it in the future if that makes sense.

At this point I've recovered the collection to my apartment in Israel. I've started sorting the collection, mostly because after reflection I decided to reframe it as something actually fun to do, as opposed to a chore or something in order to make money (it would probably not be worth the value of my time). After I sort the collection I am considering rebuilding some or perhaps all of my old sets, see what condition they're in and whether and how many pieces are missing. 

If there are any rare or valuable sets I may consider selling a few them. That said I have already seen firsthand how much my daughter is enjoying the collection, and it seems I will hold on to most or maybe even all of it. But I won't make a decision for sure until I am done sorting.

I asked this collection on Facebook and received a number of alternative suggestions that were not among those I considered initially:


Donating some or all of the collection to organizations that work with kids
Creating art with it
Opening a LEGO rental business :)
Giving some or all of it away to friends with kids


I will consider some form of hybrid options between these.

I mention these here in case they will help someone else with similar challenges.