If you are buying in an estate you shouldn't have to organise any of this, in my opinion. The builder would normally arrange for connection in your name, or else intially in his name and organise for changeover once sale is due to close. How could the builder hope to close the sale if gas or ESB are not connected? I think you should go back to the builder and clarify the matter, if he is unhelpful ask the solicitor acting for you to write to the builder and confirm what is included in the contract to purchase. Gas and electricity are essential services, not discretionary like telephone, cable etc.