Key legal question
Whether ancillary costs mentioned only in standard terms were validly agreed and chargeable to the tenants.
Extracted holding
The charges listed only in the general terms were not sufficiently and clearly agreed; no obligation arose for those items beyond the rent contract itself.
Extracted reasoning
Art. 257a(2) OR requires an explicit, exact agreement on ancillary costs. A reference to standard terms does not suffice if the tenant cannot recognize from the contract itself which costs are transferred.