My old man bought a house in FL, they plumbed the hot water line to never-never land under the slab, that was fun to fix, had to re-route via PEX thru the roof.
Ya know, one of my problems with with a lot if this stuff is I think I failed in my design if I have to futz with it. If I took a long trip and came home, I'm pretty sure I can wait the 20-30 minutes for the HWH to get warm, assuming I bothered to turn it off in the first place, which is doubtful. To each his (or her) own, but if I'm investing 40 grand and engineering my own utilities, I don't want to have to think. In all likelyhood I wouldn't be thinking about hopping on my phone and turning on the hot water just before I get home, I'd forget 9 times out of 10. If I'm gone long enough to go to the trouble of winterizing and opening my house/cabin, I'm probably going to have checklists for when I leave/get home, on which I would prioritize turning things off/on, a possible one-time expense of heating a tank of water with propane/other is not going to bother me if I really want it that bad.
I'm pretty anal, but I'm not the kind of guy who's going to drive 6 hours up to my cabin, walk my checklist, get everything turned on, go unpack and then start doing laundry. Maybe a shower, more likely food and a beverage and some TV. The little woman might disagree
!