The rights provided for by law always prevail over those established by a written or oral agreement. An agreement that states that you or your landlord have fewer rights than those given by customary law or the law is a fictitious rental agreement. As a general rule, a rental agreement can only be changed if you and your landlord agree. If you both agree, the amendment must be recorded in writing, either by drafting a new written document outlining the terms of the lease, or by amending the existing written lease. It is a good practice that a written rental agreement contains the following details: CONSIDERING that the parties now wish to conclude this contract, which will be concluded from the 15th date of 1 July 2018, remembering the oral agreement of the parties and adding additional conditions to it in the proposal; The rent increase will take effect from the next payment of the rent as soon as the contract exists. Thus, the new increase in contracts and rents will take place from 11.02.18. . .