arizona: I will be moving to Tucson, Arizona (The southeast side) in September. What is the average cost in utilities for a small 2/3 bedroom house? There will be 2 adults and a toddler. Hopefully we can use a fan to beat the heat moreso than the air. Trying to put together a budget. Thanks!|||It all depends on how low you put the thermostat and what kind of cooling system you have. The geneal rule of thumb is that an evaperative cooler uses about 1/4 of the energy as an A/C unit. I used to be able to run my evap cooler half of the day in a small but drafty 1920s house for about $40 per month. Since moving to a larger and more energy efficient house with A/C, my bill was closer to $100 but I also keep the thermostat in the low to mid 80s all day. Figure for most average size houses you are looking at $75-$100 per month. If you have a historic house then the cost will probably be $25-$50 higher due to the air leaks and construction materials used.