What you are talking about is the name change of the contract. What you said above is valid. If the developer wants to change the contract, he must sign a new house purchase contract with you, but the new house purchase contract must be obtained from the real estate bureau. Each house purchase contract is numbered. To obtain the new house purchase contract, he must take out the old house purchase contract (one for the real estate bureau, one for the developer and one for the householder).

there is also a case where the original householder sold the house to you before the house purchase contract was handed over to the real estate bureau (that is to say, the householder has a house purchase contract, the developer has two, but the real estate bureau has not, and it has not been filed), and it is also effective for the developer to directly change the name, because after the change, you will have a house purchase contract (just pay attention to whether all kinds of bills are in place. For details, you can ask developers how to speculate.