all good suggestions. some of the things I make sure to have:
at least a 12pack per person per day. dosn't mean you have to drink it all, but beer is, and always will be the currency of the river.
saraong. don't leave home without it.
take the time to find out what your friends frames are composed of, and YOU build a repair kit of misc. set screws, pins, etc.
Over the years I have compiled a disgusting amount of pelican boxes, otter boxes, and misc. small item storage. these make life really easy. organization of small items gets tricky, and these small boxes are the ticket. try to get the ones with clear lids.
GSI, also makes some nice dry storage boxes.
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