Hi. The builder is only interested in his money. Whether it comes from you or your buyer. So you just have to inform the builder that the balance payment will be done by your buyer and the agreement has to be registered with that buyer instead and not with you. You have one advantage that you have not signed an agreement with the builder. Generally in the agreement a clause is put which states that if the purchaser assigns his rights in the flat to be allotted to a third party then he will be liable to pay a transfer fee to the builder. Hope such a clause is not there in your allotment letter. Till a proper agreement is registered between the builder and purchaser, the allotment letter acts as a binding agreement between the parties. So if such a clause is present in your allotment letter then the builder can invoke the same against you and demand transfer fee from you. If such a clause is absent then you are not obligated to pay any transfer fee. However the builder in all probability may try creating issues in giving his NOC and consent for transferring the rights in the flat to your proposed buyer without first paying the transfer fee. So if the clause is absent and the builder makes a demand from you then you will have to negotiate hard with the builder. Whatever is ultimately agreed between you and your builder, if the builder agrees to transfer the rights in the flat to your buyer, then a triparty agreement will be executed between you, your buyer and the builder wherein your buyer will pay the agreed amount for you to exit from the project and will also agree to pay the balance consideration payable to the builder and this agreement will then be registered. You can also try and negotiate with the builder for directly executing and registering the agreement with your buyer in case you do not wish to disclose the sum that you have received from your buyer, to the builder. So its a tricky situation which you have to handle smartly.