Leviticus 25:30-34

But if it is not bought back for him within the space of a full year, then the house that is in the walled city passes permanently to its purchaser throughout his generations; it does not revert in the jubilee.

The houses of the villages, however, which have no surrounding wall, shall be regarded as open fields; they have redemption rights and revert in the jubilee.

As for the cities of the Levites, the Levites have a permanent right of redemption for the houses of the cities which are their possession.

What, therefore, belongs to the Levites may be redeemed, and a house sale in the city of this possession reverts in the jubilee, because the houses of the cities of the Levites are their possession among the sons of Israel.

But pasture fields of their cities shall not be sold, for that is their permanent possession. Of Poor Countrymen