The builder might have spelt out the final figure for your dream home, but what about other costs that are not related to the builder; like VAT, Service Tax applicable, corpus funds to be paid to association, registration fees and legal fees for the execution of the Sale Deed, Khatha / Mutation transfer fees, fees paid to Electricity & Water Boards, etc. Please note that sometimes they can add up to more than 10% of the actual cost paid to the builder, so do not take this lightly. Depending on the builder, the area, and stage of construction, you might be in a position to negotiate these into the payment schedules. So do not leave any stone unturned.