If the delays are due to policy-related force majeure like customs system upgrades, or if our documentation errors lead to short shipments, all additional demurrage and storage fees incurred at ports within China will be borne by sellwellauto, and the buyer will not have to pay a cent.

Yes, but this falls under EXW (Ex Works) terms. In this case, the seller's risk transfers at the moment the goods are ready at the warehouse. Any subsequent domestic trucking accidents, customs inspections at the port, or issues with obtaining export licenses will be fully borne by your designated freight forwarder.

The customs of the destination country has the right to disregard the commercial invoice and reassess the value based on its internal database (such as the customs valuation red book). Any additional duties incurred are a result of the importing country's policy and are fully borne by the buyer (importer).