Fact: 

Turning off the air conditioner when you leave could actually cost you money.

That’s because when you turn it back on, all your savings will be lost as the unit works overtime to cool your hot house. A better way to save on utilities is to turn the thermostat up or down (depending on the season) 5 to 10 degrees when you leave, says home improvement expert Danny Lipford of todayshomeowner.com.

And the best option? “Install a programmable thermostat,” he says. Even better, buy one you can control remotely with your smartphone and adjust the temperature before you get home. Because thermostats you have to touch are so 1998.