Right away, I was thinking of the LETS scheme, got beaten to it by jansman
but there's at least one system still going, in Lewes in Sussex: https://www.thelewespound.org/The last entry in the blog is dated July this year, so I presume they're still going.
I think the important thing is the "double coincidence of wants", yes - with the NHS thing, for instance, maybe somebody's okay to give me social care and bedrest, but what if I bring an infection from the hospital with me and I suddenly need urgent nursing care? I doubt there's going to be much double coincidence there.
I haven't done any bartering, but as a family we do a lot of exchanging favours - though petrol and van hire get shared between everyone, for the sake of fairness.
There's also mates rates, in today's world - my own line of work - counselling and therapy! - isn't where this is normally expected, but I fell into it by accident. A friend who was also a colleague went to live abroad for a year and kept her online clients, as she had good online access. I gave her supervision by email, and it was *give*, as it was about every other month. When she returned, though, it gradually became 1.5 hours a fortnight, in person, and it was too much to do for free, especially as there was nothing coming the other way, so we started doing mates rates, *very* low amount.
) then on the post you want to quote there's a box on the top right corner "QUOTE, click on that and voila. Saves you typing it all out"