Questione giuridica chiave
Whether ancillary costs were validly agreed and chargeable to the tenant under the lease contract.
Decisione estratta
No. The contract did not clearly and specifically identify which ancillary costs were to be borne by the tenant, and the payment of monthly advances did not replace that missing agreement.
Motivazione estratta
Under Art. 257a para. 2 CO ancillary costs are payable by the tenant only if specially agreed. The contract mentioned only a monthly advance and final balancing payment, without specifying the cost items. Prior payments and alleged continuity with an earlier contract could not establish the missing clear agreement.