To make an offer you need to sign a contract and write onto that contract the price you want to pay and the terms and conditions (finance clause, deposit amount, date of settlement etc). A verbal offer is not legally binding with an agent or seller and may only be useful in negotiating a price and conditions prior to putting it down on paper. When purchasing through an agent they will present you with a contract document to complete. Make sure you place your full name (including middle names), and the clauses required on the document at this time as it could be difficult and costly to change once signed by you and agreed to by the seller.