Each type you listed (save a couple) will have its uses in a community (group if you will), generally having a small trusted group with each having several skills in the various fields (prepper, homesteader, and survivalist) I believe would be an effective team, though as each group works together would it not be best to ensure that each has overlapping skills in case of injury, death, or other reasoning they can not fulfill their duties?
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Earthquakes, tornadoes, and hurricanes can cause you to leave your home or even be trapped there. Roads could be blocked due to fallen trees, power lines, or even damaged earth from the natural disaster. Rescue crews can not be in all places at once. You may have to wait it out for quite a while before its over. You won't be able to go to the store or to the corner market.