How to collect the property management fee if the design of the house sewer pipe is unreasonable, and whether to refuse to pay the property management fee?

1. If the design of the sewer pipe is unreasonable, the design defects can be technically appraised by professional institutions. If it is a real design defect, it can be solved through negotiation with the developer through the purchase contract. If negotiation fails, the design defects can be remedied through litigation, and the liability for breach of contract and compensation for economic losses can be assumed. 2. The property management company also has corresponding responsibilities for this case. When the service of the property management company is defective, the owner has the right to defend the payment of the property management fee, but he should not refuse to pay it in full. Instead, he should refuse to pay the management fee of the defective project according to the specific circumstances. For inseparable or inseparable property management fees, he may refuse to pay part of the property management fees in proportion. The specific amount of refusal should be negotiated with the property management company on behalf of the owner. At the same time, the housing management department and the price department should redefine the composition of property management fees and unify the charging standards in order to facilitate the smooth settlement of such disputes.