A few quotes from the Rabbi on 'Tzedakah and Healing'
in which he rules to not raise the rent of a house when the landlord remained silent although prices had risen.
Concerning the occupancy of a house, rented from him by Moussa for a period of time at a low rate, and now that prices of homes have risen, he seeks to increase the rent…
I ruled that he cannot now add to the rental fees since, despite the rise in prices of homes, he remained silent and didn't raise the rent and, as a matter of fact, collected from him every month at the low rate; he may therefore not add anything at all to the fee.
Tokfo shel Yoseph, Part 1, paragraph 34, p. 158. Bnei Issachar Sephardi Library Publishing, Jerusalem, 2004
