I wouldn't recommend putting much aside for barter, but recently I've considered buying a bunch of cheap butane lighters for my own use and barter.
As far as where to trade, unless it's somebody I know I agree that trading at home may not be the best idea.
I guess a lot depends on how bad will the future be. If 1 is today and 10 is MadMax, we might only be seeing 5. Maybe there won't be starving, just some hungry people. I've thought a lot about this, though it may seem good to prepare for the worst case scenario, we shouldn't assume that's what it will be.
Lastly if you do barter, don't be concerned about getting a great deal. There's nothing wrong with coming out on the short end. Building good relationships is important in the days ahead. If someone later feels they got take advantage of, may not be too anxious to help you out when you need them.