First, as for the individual:
Those who practice this must have renunciation,
Keeping their bodies far from the bustle of civilization;
Keeping their minds far off from the host of complexities;
In such a way, samadhi will quickly be established.
With body and speech distracted by the bustle of activities, and mind distracted by a thousand nets of complexities, if we don’t even establish shamatha, why even mention samadhi? Therefore, keep the body far from the bustle of civilization. Stay alone in a completely solitary place like a remote forest. Keep the mind far from the host of complexities. Then within our being, moistened by shamatha, profound samadhi will be established. The Samadhiraja Sutra says:
Prince, therefore those desiring samadhi should forsake places disturbed by bustling activity, and exert themselves while remaining alone in a solitary place.
It will not be established, while living in a house.
The same text says:
Whoever stays inside or outside a house,
As for attaining completely pure true enlightenment,
Such a buddha has never arisen yet.
They do not exist, and never will.