The neat part of anarchy is that it does not always work in favor of the anarchist. For example, if somebody squats in your home, and the law is too feeble to kick them out, then it is also likely too feeble that if you hire somebody to kick them out, to do anything about it.
That is, she should hire some brutes, with instructions that they are to purge the house of the squatters, destroy all their stuff, and if they resist, persuade them that it is unwise to return.
And that they have license to do this as they see fit.
When government does not protect the citizenry from criminals, or worse, when government takes the side of the criminals against the citizenry, vigilantism is the result. And while vigilantism just seeks the restoration of order and non-violence, if the authorities and the criminals resist this restoration of order, it is not the fault of the vigilantes when they must use force to reestablish order.
in this case, anarchy is only one way. If the woman of means hires thugs like you suggest, she will get sued for millions, and may end up in jail. A woman with nothing steals a house, no one cares.