My mother recently did this to me, like, 3 weeks ago, not the planned part, but the unplanned. She knew she was dying, she had a rare form of cancer that has a very low long term survival rate and she had it for long enough to have planned for this. She never made a will, even though she had articles cut out about how important it was to have one (I think she just didn't want to confront her mortality like that, she was scared of dying, I don’t blame her, and I miss her terribly but at least she’s not in pain anymore). By the time she knew it was the end there was no time left to make one.
Her finances were kept very well organized. So we’re great there, even had a folder going with every scrap of paperwork we’d possibly need for her 2017 returns, but she did that every year for every return. What she didn’t keep well was the house. She was the type to put off every type of little project or issue until it was catastrophic. So now I have a house that has had little to no maintenance for over 20 years to try and fix up to sell, is full completely full of stuff most of which just has to go, and I am so overwhelmed and stressed about it. I barely even know where to start.