Leviticus 25:30-34

And if it be not redeemed within the space of a full year, then the house that is in the walled city shall be established for ever to him that bought it throughout his generations: it shall not go out in the jubile.

But the houses of the villages which have no wall round about them shall be counted as the fields of the country: they may be redeemed, and they shall go out in the jubile.

Notwithstanding the cities of the Levites, and the houses of the cities of their possession, may the Levites redeem at any time.

And if a man purchase of the Levites, then the house that was sold, and the city of his possession, shall go out in the year of jubile: for the houses of the cities of the Levites are their possession among the children of Israel.

But the field of the suburbs of their cities may not be sold; for it is their perpetual possession.