Legal analysis: After mortgage payment, the developer should issue a full invoice. After the borrower signs a loan contract with the bank, the bank will allocate all the loans to the developer in one lump sum. According to the law, the developer should issue an invoice to the owner to prove that the owner has obtained the loan right. And only when the owner gets the invoice issued by the developer can he repay the bank. And every time the owner pays the first installment payment to the bank, the bank will issue an invoice accordingly.

Legal basis: Article 19 of the Measures for the Administration of Invoices in People's Republic of China (PRC), when units and individuals that sell goods, provide services and engage in other business activities collect money from outside, the payee shall issue invoices to the payer. Twentieth units and individuals engaged in production and business activities to buy goods, receive services and engage in other business activities, should ask for invoices from the payee.