If you select the rent adjustment type Index adjusted, you must first select the adjustment frequency (once a year, once a month, every two, three or six months).
Select the adjustment months from the list according to the chosen adjustment frequency.
Under Index, you can select the Cost-of-living index or the Real estate maintenance cost index.
The base index determines the starting point for index-related adjustments. Select the release date of the index that is used, when the index-related adjustments become effective.
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