Legal analysis: Under normal circumstances, the contract can be seen on the day of signing, but after the customer signs the commercial housing purchase contract, the developer will submit the purchase contract to the Housing Authority for filing, which usually takes 30 days. If the customer is in mortgage to buy a house, after the contract is filed with the Housing Authority, all the loan information of the customer needs to be submitted to the mortgage bank for review, and the mortgage loan procedures need to be handled. The processing time of this process generally takes about 30 days (depending on the work of different banks). After all the above procedures are completed, the signing center will inform the customer to receive the purchase contract. Generally speaking, you can sign a house purchase contract with the developer after paying the down payment. Generally, there are two formal contracts, one for the original developer and the other for the bank, so the buyers can't get the purchase contract before repaying the loan. However, you can borrow the original contract from the developer and copy it about one month after signing the contract. Therefore, under normal circumstances, the developer will take the contract to the Housing Authority for filing, and it will take half a month to get the contract. If it is a mortgage purchase, the time will be longer, about a month.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 410 Where the debtor fails to perform the due debt or realize the mortgage right according to the agreement of the parties, the mortgagee may agree with the mortgagor to discount the mortgaged property or give priority to compensation with the price of auction or sale of the mortgaged property. If the agreement harms the interests of other creditors, other creditors may request the people's court to cancel the agreement. If the mortgagee and the mortgagor cannot reach an agreement on the way to realize the mortgage, the mortgagee may request the people's court to auction or sell the mortgaged property. Where the mortgaged property is discounted or sold, it shall refer to the market price.

Article 413 After the mortgaged property is discounted, auctioned or sold, the part of the price exceeding the amount of creditor's rights shall be owned by the mortgagor, and the insufficient part shall be paid off by the debtor.