Here are some airconditioning tips: make sure that all air spacers under doors and around windows are filled with simple insulation that you can buy in Lowes or Home Depot. You can get a fairly significant roll for about $5.00. Also see if your airconditioning pipes into the home are wrapped. Older homes do not have efficient windows. Look for a newer home with Low E Windows or a similar brand which keeps out the sun's rays and keeps the cool air inside. Ask whomever is showing you the property the SEER value of the airconditioner. The new build code for Las Vegas is a 13 SEER or better. The higher the SEER, the more efficient the unit. Also check the tonnage to make sure that the home has the correct tonnage for a home of its size. A newer airconditioner will be significantly more efficient than an old airconditioner. If you are choosing a 2 story home, make sure that it has two airconditioners. This way, one or the other can be set to higher or lower values depending on where the family is at any given time. Don't keep your thermostates freezing cold. Moderately cold is fine almost all the time. Turn your thermostats up higher when you are at work during the day. Turn them lower when you come in. The home will cool down rapidly. Don't keep the windows or doors open when the airconditioning is running. If you want the windows open, get screens. But don't open them while the airconditioning is on. I hope these tips help you.