I was going to respond to you point by point, but I realised halfway through you might not read it anyway, so I will focus on two misunderstandings you seem to hold, that affect all of your questions:
First, this is a very revealing question:
> Can I give out loans with crazy interest rates? If yes, you just legalised debt bondage, a form of slavery.
For a loan to turn into slavery, you presuppose a system that can by threat of violence convert debt to forced work. In a true anarchy, there's just no way to go from debt to forced work.
Under anarchy, debt is a voluntary cooperative agreement between two people where they think one can use the pooled resources of both more effectively than they could alone, in exchange for a cut of the fruit of the labour.
Both parties enter into this agreement fully aware that those fruit may never materialise and, critically, that there is no way to employ violence to ascertain that they do.
However, a community is not made out of two people. If one person routinely dishonours their loan agreements, they will find it hard to cooperate with other vital functions of society, for example to acquire food or tools or utilities or communication.
This leads into your second misunderstanding. You seem to imagine that a person under no regulation can "build up as far as I want".
As an individual, there is only so far up you can build. Realistically, you can personally forage material and build for at most 10 hours per day and then you need to forage food and get rest. As an individual, you cannot use machinery because you cannot, as an individual, get the petroleum to drive the machinery.
If you are going to build anything of consequence, you need to enlist the help of other people. In a capitalist society, this is somewhat easy: you can convert capital into tall buildings, regardless of what the local community wants. This is why capitalism needs regulation, to account for what the local community wants.
In an anarchist organisation, you will find it really hard to recruit builders that will voluntarily ruin their own local environment.
This theme continues throughout your comment:
- if you block my solar panels and the community disagrees with your reasoning, you might find it hard to live comfortably in that community because other people will be less inclined to help you acquire your creature comforts.
- if you start a pyramid scheme and call it a bank, the community bank rating association will give it a shitty score.
- if you repeatedly lie about the items you are selling, you will get a bad marketplace rating too -- just like what happens already in less regulated markets today.
- free banking was never the disaster currency monopolists would like it to be. Sure, it had its fuckups, but so does the current system. The problems may even have been more frequent, but also of a much lower magnitude.