Lower travel costs. For example, if you’ve included five visits to a client site in another state, can you reduce the number of visits you make without reducing the quality of the product you deliver? Can you get cheaper airline tickets if you book farther in advance? Can you reduce the number of people traveling?

Lower equipment costs. Can you find a vendor who will sell or rent equipment to you at a lower price than you allocated in your project? Can you rent equipment you planned to buy, and if so, will renting be less expensive than buying?

Lower human resource costs. Can you substitute an employee who costs less to do a job than the consultant you planned on hiring? Although using a less-experienced resource might make a task take longer, will the additional time needed to complete the task by that less-experienced resource cancel out the benefit of using a lower-cost resource? Also, can you reduce overtime, which is typically more expensive than work done during regular hours?

If you must use more expensive resources on fixed units, effort-driven tasks, can they get the job done faster than you’ve planned?