The government should have a role in the management of natural resources such as land. The government should not have a role in managing abstract activities such as labor, education, healthcare, charity, retirement investing, etc, but unfortunately it does. If we were to downsize the government and remove its tentacles from all of these abstract activities, its continued role in natural resource management would still leave the government much smaller than it currently is, and therefore the police state much less powerful than it currently is. For example, instead of sending the cops after someone for not paying the tax penalty for not purchasing health insurance per the Affordable Care Act that the person never agreed to, the cops would be used to enforce the terms of the land contract that the person voluntarily agreed to. By restricting the force of law to concrete, real world physical interactions, there would be many fewer opportunities for the current over-policing that comes with the government’s current practice of coercively micromanaging way too many abstract activities and private decisions. Both the classic libertarian way and the geolibertarian way would leave the government much smaller.

Regarding the control over who a neighbor’s house is sold to, theoretically there’s the possibility of Home Owners’ Associations setting conditions on home resale. Using the justification of agreement with the developer’s terms, HOAs can currently dictate the color of paint on people’s houses.

In most cases, one can’t directly control who his neighbor sells to without probably resorting to coercion himself. Such coercion can run both ways, by the way. There’s the proverbial brick through the window of the new black neighbors, and there’s also the anti-white violence that keeps inexpensive properties in black neighborhoods from being “re-gentrified”. There are plenty of whites who would be interested in a <$100K home within short distance of downtown Baltimore, but the anti-white crime makes it practically impossible for most. The properties’ affordability to blacks that is enforced by anti-white violence is an example of black privilege.

One’s best bet for morally “controlling” the quality of his neighbors is peaceful economic pressure. In a hypothetical meritocratic country where people can’t get above-average rich through government employment, where special interests can’t be enriched by bribing the government, where current counter-economic activities become legal so they no longer offer a bloated profit-motive, and where an efficient police force actually does its job of preventing and punishing crimes against victims, the way to get above-average rich is by providing honest utility that people voluntarily compensate for. In such a hypothetical country, if one lives in a neighborhood that only honest, useful people can afford, then his neighbors will likely be quality people. If this meritocratic way results in some places being not diverse, then so be it. People in poorer neighborhoods would also be safer than they are now because of the improved police force that wouldn’t be demoralized or distracted from its true mandate. If the person in this example is hellbent on specifically racially discriminating, he can join a peaceful local club of same-race people, which should be legal out of respect for the right of free association.

People can also use social pressure, such as setting a tone of who’s “welcome” in certain locales by using non-violent methods such as social ostracism. It’s a jerk move, but at least it doesn’t injure anyone or damage property.

Otherwise you’d need legally set-aside racial enclaves such as “the black people’s zone of southern Alabama” or “the white people’s zone of northern Maine” or whatever. The logistics of setting these up would be difficult, involving a lot of eminent domain to compensate re-located people, but if people want to vote these things in for the sake of peace, that’s their prerogative.