My last bill was $770 for 3 months. 3 bedroom house with a small study/4th bedroom, 1 bathroom, large kitchen and lounge room, basic hallway and laundry. We have aircon, in the lounge and bedroom area only, which was running on most of the hot days of Summer. I do use the dryer a fair bit, and wash in warm water about 3 loads a day.
Have electric hotwater, and cooking. Our bill jumped from $500 last Summer. And Joy oh Joy, they read the meter this morning!