My insight based on my personal experience: stuff doesn't matter. Get there quick, pick out a few things that are meaningful to you, and let the rest go. If your grandma takes stuff, it's truthfully not your business where it goes when she passes.
I just saw about $300,000 of our family money go to a complete stranger, because she had access and lived close to the deceased, where I did not. That happens ALL THE TIME in these situations. People take things, and other people are mad, and drama ensues.
Let it go, for your mental health. Take a few things that are precious to you, and forget the other stuff. If I can emotionally let 1/3 of a million dollars go, you should be able to let some belongings go.
And when two people want the same thing, hopefully the two people will be civil enough to let the object go to whomever it most suits.
It is NOT WORTH the emotional stress.