To clarify: a fiscal host acts as the legal entity and bank account for other smaller entities. So an organization that's already established as a co-op will hold your money in their bank account so that you don't have to worry about handling taxes or book keeping while you get started and if you need to sign a contract or something it's technically with the parent organization so you can use their business vehicle. I know of lots of non-profit ones, but none specifically for developing co-ops.
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