The law stipulates that, in the case of an open-ended rental agreement, the landlord has the right to increase the rent once a year. There are two ways to do this: 1) Notify the tenant about the increase 30 days in advance, 2) Agree with the tenant in advance upon the conclusion of the rental agreement that the rent will increase periodically.
In the first case, the landlord must remember that the notice of increase must be in writing. The notice must include: the extent of the rent increase and the amount of the new rent; a fixed date for the increase (at least 30 days after the notice is given); the reason and calculation of the rent increase; the procedure for contesting the rent increase. Certainly, the tenant may not be threatened, and if the rent increase is contested the rental agreement will be terminated. In such case, the notice of the rent increase will become void.
In the second case, the parties may agree on the extent of the rent increase or the basis for its calculation (specific amount, percentage, or index) in the rental agreement. The landlord and the tenant agree upon whether the rent will increase within the term specified in the agreement or upon informing the tenant. If the parties have agreed that the rent will increase upon notifying the tenant, the landlord must give 30 days' notice. The notification must be provided in writing.
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