Sign by the owner and write down the contact number. The owners' committee needs two-thirds of the owners' consent, which can be signed by the owners during the certification process. After writing down the account number corresponding to each owner, the owners will sign and write down the contact number. Once the owner signs and writes down the personal contact number, it means that the owner already knows and agrees, and can confirm and prove it. The conditions that the owners' committee must meet are that it has full capacity for civil conduct, abides by relevant national laws and regulations, and has certain organizational ability.