I want to buy a house, and the property right certificate has not been processed yet. The contract sent by the seller is as follows. What can I add to protect my interests after consultation?

Hello, the payment method of this contract is not clearly defined; Each payment shall be signed immediately; Has the other party paid off the mortgage? Article 4: Sign all kinds of contract documents in time and go through all kinds of formalities. When handling the real estate license, we will try our best to help change the name of the real estate license to the name of the buyer. If we can't change the name directly, we will cooperate to assist in the transfer, and to what extent we need assistance. If you don't cooperate, you must make it clear. The rest depends on whether you are satisfied. If you are not satisfied, you can negotiate with the other party to amend the contract. If you are confident that you can perform the contract as agreed, you can appropriately increase the liability for breach of contract. If in doubt, please consult our lawyer.