Or HaChaim on Numbers 35:2/אור החיים על במדבר ל״ה:ב׳

1 ונתנו ללוים מנחלת אחוזתם, "that they give to the Levites of the inheritance of their possession, etc." The meaning of this verse is that while it is true that the Levites were not to have a claim to an inheritance in the land, there was nothing to prevent them from accepting parcels of land as a gift from the other tribes. This is in the same category as the rule that one should provide a livelihood for people who have not been fortunate enough to provide it for themselves. When the Torah is specific, writing ערים לשבת, "cities to dwell in," the meaning is that seeing the Levites have to live some place they need to be allocated cities for themselves. The Torah repeats the statement to indicate that the first time the Torah writes לשבת is to justify why these cities have to be given to the Levites; when the Torah continues with והיו הערים להם לשבת (verse 3) the Torah emphasises that these "cities" must be fit to dwell in. We are told in Makkot 12 that the meaning is that cities must be reserved for residential purposes and that it is forbidden to convert land set aside for residential purposes into מגרשים, open playfields, etc.