You want your answer to exhibit determination. Frame yourself as resourceful, with a propensity to think fast on your feet. Demonstrate that you aren't easily discouraged. You want to convey that you believe where there is a will, there is a way. Meeting deadlines, overperforming, learning, and innovating is the aim of the message in your example.

"Besides keeping payroll down and productivity up, I'd look over everything and study it to see if there was another way to go about it. So often methods to cut costs are hiding in plain sight. For example, I worked for my grandpa at his convenience store over the summers in college. One day, I had an idea. We were using an overpriced vendor for our office and backroom supplies. I knew someone in college whose dad managed an office supply company, and I was able to negotiate a bulk buyer's discount for our company while cutting out the vendor. Grandpappy was thrilled."