Home Temperature and Buyers' Temperaments.
Think about your own personal experience; have you ever cut short your stay at a place or event simply because it was too hot or way too cold? Having a comfortable temperature when showing your house is extremely important. You don't want buyers to temperaments to quickly switch from positive to negative based on the temperature they are experiencing.
Since my market is South Florida, I will focus on the hot weather. On a previous blog, I recommended you keep curtains and shades open to maximize the light in your home during a showing. Keep that in mind when setting the thermostat and also think about the midday high temperature peaks that might make your home feel significant degrees hotter. If it's a hot summer day, keep your ceiling fans on. You also want to make sure your AC units and fans are working properly. You definitely don't want any of that humid smell associated with AC units that need maintenance.
You might want to leave a bucket with ice and some water bottles on the counter for buyers and realtors with a sign that says 'Welcome'. An iced pitcher of sweet ice tea or water with lemons and mint leaves is also an inviting touch and a nice display of southern hospitality.
Remember the more comfortable buyers feel in your home, the more they can envision themselves living in it.
P.S. Here's a helpful video I found regarding the direction of your ceiling fan.