Regarding credit and contracts, you are right, which is why I said enforceable contracts and credit (though in the case of crypto, you can speak of contracts entirely within that realm that are self-enforcing without violence, so you are right about that, though it doesn't extend to actual physically material).

Regarding property and the NAP, my thoughts are written here, but the gist is that you've basically taken a non-violence principle and altered it to accept violence against people that cross imaginary lines. And of course, whoever is committing or threatening that violence to enforce those lines, whether you choose to call it a police force, a military, or a "private security company" is by definition acting as an agent of a state, an organization with a monopoly on violence at that place and time.