Or HaChaim on Numbers 35:6/אור החיים על במדבר ל״ה:ו׳

1 ואת הערים…את שש ערי המקלט, "and the cities…the six cities of refuge, etc." From this verse we learn that these six cities were to serve primarily the involuntary murderers who had to be exiled there and not the Levites. Seeing that in verse 7 the Torah mentions that the grand total of the number of cities allocated to the Levites is 48, it is clear that the Levites were also entitled to live in the six cities of refuge. Apparently, the Torah wrote matters in such a way that we understand that the Levites and the inadvertent murderers (Israelites) had equal rights in the six cities of refuge. This is why the Torah stressed the rights of the inadvertent murderers in the first verse whereas in the second verse it appears to stress the rights of the Levites. From all this it is clear that the exiles do not have the right to charge rent to the Levites. All the opinions discussing this subject in Makkot 13 are agreed on this point. I may add that it is my view that in the event that there is a surfeit of exiles in any of the six cities of refuge, a Levite may be forced to leave in order to make room for an inadvertent murderer.