Hi, Dicey. My thought process is based on having a skimpy minimalistic stash - perhaps ok for a hardy flexible person, but risky if my roll-with-it skills fade with age. Also, family history of Alzheimer's. Therefore:
Track 1, Alzheimers is Expensive - as long as my mind is sharp, I can scrape by. Sure my 375-to-400k stash (450 but with some deferred house maintenance and planned insurance premiums now mentally deducted) leaves little margin for error, but I can deal with it. I think I'm going to go increase it anyway through some further work, but if I fail, I can still make ends meet...unless Uncle Al Z Heimer butts in.
At that point, my expenses will go up and so will my mistakes. Sure the disease will prevent me from living too long, but an extra 100k to 150k might be needed. Insurance would essentially trade tens of thousands in premiums for a payback+100k in time of need, providing just enough to pay for the likely cost of care as I estimate it.
Track 2, Thanks to Sis - my sister performed wonders and I moderately helped out in turning my Dad's adequate resources into good quality care during his Alzheimers. We concluded that a competent advocate makes a big difference. Our agreed principle in confirming that we will be each other's advocate if needed and able is that we will each take responsibility for providing the funds for our own care. The advocate sibling's job will be to administrate funds and choose/supervise caretakers, not provide funds or daily hands-on work. Buying an insurance policy will a) improve the odds of fulfilling my commitment to provide adequate funds, and b) demonstrate that I Really Tried The Best I Could. Sis is hesitant about the scrape-by-on-400k plan, but will likely accept insurance as a substantial responsible effort.
Track 3, Mollify Pessimistic BIL - Sis's husband believes that my jobless life implies I will soon be broke and homeless. My failure to find employment of note since 2013 clearly indicates that I must be planning to mooch off them by living in their house as soon as I do go broke. Since invasion of his space greatly disturbs his treasured peace, this is his biggest fear and apparently troubles him a lot. Sis believes an insurance policy will make him believe that maybe I mean it about paying my own way, and in any case reduce any rational fears. Irrational fears we can't fix, but let's do our part to limit rational ones.
4) Track 4, Because cFireSim and Responsibility - I hesitated to waste money on this at first, despite all the reasoning above, until I sat down to compare scenarios in cFireSim. I hadn't become clear on the 100k part above when I sat down. But when I looked up length of care data for Alzheimers, multiplied by cost of care data from experience, and included the costs to account for an Alzheimers scenario vs a non-Alzheimers one, I realized that getting the insurance made a difference even though it didn't change the overall odds of success. Based on a guess of 25% chance to suffer from Alzheimers (family details redacted), the main effect of insurance isn't to change the probability of financial failure, it's to shift the probability of failure from one scenario to another. Without insurance, I have maybe a 4% chance of financial failure with sharp mind scenario (4 out of 75), 3% with Alzheimers (3 out of 25). With insurance, financial failure with sharp mind jumped to 6%, but failure with Alzheimers dropped to 1 percent. Either way it's about 7 percent total after including the Alzheimers expense the way I calculated it, but insurance means that my sister is protected while I take responsibility for managing the failure case.
Numbers for this last branch are still being firmed up as I get actual quotes. Some of the scenario planning is more seat of the pants than it should be. But now that I realize the responsibility effect of the insurance, and also realize that the responsibility shift is intuitively obvious to Sis and Hubby, I am hot on the trail of the insurance. Base goal is insurance by Christmas, stretch goal insurance by Thanksgiving.