Start by comparing the full cost over the same period, such as a month or year, rather than focusing only on the advertised price. Include usage charges, delivery fees, subscriptions, discounts that may expire and any upfront or cancellation costs. Check that each option offers a similar product or service, then calculate the difference using your own typical usage. For energy, the Australian Government’s Energy Made Easy website can help compare plans, while other purchases may be worth checking with the provider before you decide.