Interesting thread. Seems to have drifted quite a bit from the original question... and I guess I'll contribute to that drift.
We're farmers. Not precisely "subsistence" farmers, but we've worked 12-16 hours a day, 7 days a week, for as long as we've owned our own farm- 31 years last July.
We're very familiar with back breaking work, long, hard hours, working in heat, cold, rain, snow and through flu, broken bones and other problems. (hubby is currently hobbling around on crutches with a knee brace, doing whatever jobs he can handle so I can keep up with the milking without falling completely apart physically. We're getting too danged old for this).
When the kids were younger, we had FUN. We'd sneak a half hour break after lunch in a haying afternoon for a quick dip in the farm pond (usually while waiting for the hay to finish drying down). We've had wood stacking contests, and there was always enough time (well, we'd MAKE the time) to identify a strange butterfly or caterpillar, check out some animal tracks, or watch a pair of circling hawks hunting.
The kids- all grown now- still joke that "family togetherness time" happened most often when hubby or I would dash in from the barn, announce that we "had feet" (a calving cow was finally to a stage where help was needed).. and whoever was handy would all dress quickly and run out to help.
We picked wild berries, made cider and jam, built and repaired machinery... all with various family combinations helping as needed.
Sure, we heard some complaints about "slave labor" from the teens, but oddly enough- or not- they all voluntarily come back to the farm to help us with big seasonal chores, like hauling wood, or building on some big job.
Family is so important, but almost no one will get along with everyone in their family. Minor differences can be either ignored or worked out (I have one DIL who is extremely liberal and who loves Hitlery and the Obamination. We just don't discuss it- at this point, no one will change their minds, and it doesn't have anything to do with making applesauce or weeding the garden, anyway). Some, of course, have issues which are more serious than that.
I have one brother, and he will NOT be welcome here, if TSHTF. It's a matter of survival- he's a "gun nut" (in a way that gives all other shooting enthusiasts and even survivalists a bad name), a compulsive paranoid with a serious narcissistic personality disorder, and he believes rules only apply to other people. He also has literally NO skills aside from his shooting skills. I can easily envision him alienating every one of our neighbors as well as crucial parts of whatever societal structure survives, very possibly to the point of causing huge problems. Oh, and he's lazy to the point that even now, living with my 84 year old mother- who is pretty much raising his young child, because his wife (who he lives apart from) is even worse than him- he does NO work. Mom does everything- yard work, lawn mowing, etc. Since she's getting increasingly frail, that means she pays someone else to do most of it now- out of her pocket.
Even if he was the only "family" we had and we needed someone to help with all the necessary work, including guard duty- I couldn't afford the risk of having him as part of the team.
So... everyone has to evaluate every relationship they have. As Meemur said, as undesirable as trying to go it alone is, it could be better than having a bunch of contentious, rebellious, lazy folks endangering you with their issues.
On the "three meals a day" idea- I understand the concept behind the thought, although I agree that having nutritious, "high value" snacks around for a coffee break in mid morning and mid afternoon may be necessary to keep people going. The idea, though, is sound- ONE person needs to be the quartermaster, as it were- in "control" of supplies, and that means knowing the full inventory, planning what needs to be rationed, what needs replenishing (if possible), and keeping things "fair". Folks in this society have been so used to "have it your way!" for so long, that many mothers are essentially acting as short order cooks every day. In a survival situation, it's vital that everyone eats the same foods, and that portions are shared out according to physical needs, not "likes" and "wants". It would sound hilariously funny to anyone from the pioneering 1800's era that we'd even have to state that- they wouldn't imagine any other way of doing things.
Bible study mandatory... I dunno. Our own personal faith is both deep, and deeply personal. If there are youngsters in the family, or "young" Christians, Bible study is important. But it needs to be part of the general spiritual life, not used as a way to keep people in line- and yes, too often, that's exactly how it's used. If some members of the team aren't Christians, you're unlikely to convert them by browbeating them and repeating Bible passages AT them. If your own Christian life isn't enough of an example for them to wonder why things don't make you fall apart no matter what- nothing you SAY is going to help.
Money division/issues? If TS really DOES HTF, what "money" are you talking about? Social security, etc? Ha! Anyone holding back personal funds from a communal living arrangement in a SHTF situation (not talking about something local and temporary like Katrina) in the hope that they'll be set up "after things improve" is delusional. Anyone holding back funds in that situation where there are physical needs and products still available is sabotaging the potential for everyone to survive. If that's explained to them, and they still believe it's "their money"... they're best allowed to withdraw from the group and take their resources to use as they wish for the own survival- or not.
I DO like the list Alpha posted. I don't see it as "people bringing all that crap" along.. I see it as everyone providing as many necessary supplies as possible, for their own survival and comfort. In our own situation, I've worked hard to have as much of the household goods (blankets, toiletries, etc) on hand for as many family members as we expect might end up here. So my own "letter to family" has concentrated on telling them to bring all the Rx and OTC meds they might want/need (again, I've prepped a lot of that, but some may have personal needs), plenty of SHOES and BOOTS and warm outerwear, birth control, etc... with any food items, etc as they can fit in their vehicle.
For a communal living arrangement to survive past the first, critical days (which probably will be, as crazy as it sounds, the EASY part; mostly because everyone will be focused on survival) it's going to be important to have a combination of immutable rules and a lot of flexibility. Providing privacy for married couples is going to be important. Staying out of personal disagreements between married couples, or parents and children, is important- UNLESS it reaches a degree which threatens the stability of the community. It is best if parents are the ones to enforce the rules on their own children, but a strong leader (preferably either the owner of the bugout/bugin location, or an older family member with excellent diplomatic skills) may have to step in and insist on some kids following the rules, especially if their families have been the stupidly permissive type.
Thinking ahead about all of this NOW is vital. We've got some practice, which certainly helps- when several of our grown kids/spouses are visiting (usually with some project in mind- "sitting around watching videos" hasn't ever been a popular pasttime here, except for an occasional family movie night), they automatically ask "what's on the list" for today. Hubby and I have our own "to-do" lists, which we consult the other on... mine usually involves the household chores, gardens, harvesting wild foods and herbs, vet work on animals, etc. Hubby's involves the farm, machinery, field work. We talk over our plans for the day and week, and work it out so we're available to help the other with projects where it's needed. For example, I may rake hay in the morning, and hubby will plan on taking an hour after lunch to help run a couple bushels of tomatoes through the strainer. Then I finish canning tomato sauce, while he bales hay. With extra people here, we just expand on that process. It works.
As far as a basic "Family Book of Rules".. the 10 Commandments and the Golden Rule should pretty well cover it.
Summerthyme