I love working in the efficiency space. It's really encouraging for anyone running projects that make a difference to living with passive heat and cooling. The incentives are there for the taking in some states in Australia. So why budget for these efficiencies? It depends on whether it is your home or a project for flipping. If the end game of your project is to sell, you need to invest in visible efficiency measures. If it is to own, the best bang for buck upgrades are invisible.