So many potentially viable suggestions. Let me at least partially summarize but FIRST:
Do we all think this insane rise in prices of late (dull places like where I used to live in the midwest have DOUBLED in the past year. Is that sustainable? I personally think not, but YMMV.
1) Stay on the boat and wait for the insanity to cool a bit - downside, of course, maybe it's NOT insanity and will get worse. What are the chances that insane will become psychotically insane in a year or two?
2) OP wants to stay close to kids. Let's see how much kids want parents to stay close to them. Rent space from the kids - hopefully the one with the couple of extra rooms and fewest kids you have to babysit. After all, how much smaller will a couple of rooms be than a boat
Rent should be dirt cheap - again, assuming kids REALLY want you close. If NOT, I see that as a "release of responsibility" to live "close." You can "go east middle-aged man, go east" until you find less insane prices. SO, you have to drive 250 miles to see the kids/GK on every other weekend. It will have been your KIDS' decision.
3) Rent. Yes, if the market turns out to be psychotic, not just crazy? Well, I guess you lose - temporarily. What goes up, must come down - hopefully in your life time. If NOT, rents are almost always the BEST bargain when housing purchase prices are insane. Rents rarely ratchet up as fast as housing costs though there are exceptions.
4) Move to a LCOL area - I mean, think Mississippi - maybe even rent, though the "bargain" effect won't be as great where housing is cheap. Fill your coffers on the savings and bide your time to move back. Remember, the planes do fly both directions and you have lots of time to get bargain flights on Tuesdays - 45 days ahead of travel (well, once Covid shakes out.)
5) You're already used to living in quarters most would consider a good sized walk-in closet (aka your boat.) Buy a decent sized "parkable" motor home or 5th wheel to live in for 2 years - or when house prices restabilize. Gotta be lots of campgrounds in the NW with all the hook ups. Not cheap rent for what you get, but WAY cheaper than mortgage. If you buy a nice used RV, you might even make money on it when you sell. Oh, and you an "See the USA" while you wait for the insanity to subside. Heh, heh, not sure what you consider good "sailing" but IMO, once you're out 20 miles, it all looks the same. Even corn fields would look good to me after a month at sea, but that's just me.
All of this is somewhat contingent on whether you think ridiculous prices will stay that way. I recall trying to save for my first house as prices took off. Mom and Dad helped us out. Just about the time we thought we were "house rich", the first housing-bubble-pop took place. We were one of 14 people in our entire county that managed to sell our "overpriced" house - but we had to take a contract to do it. Worked out well for us, but it could have been a disaster. POINT: Housing bubbles always end - hopefully sooner than later in your case. Good luck and keep us posted as YMMV.