Setting thermostat in summer

This will be my first summer with the kitties and I was wondering what temperature I should set the thermostat at. I will be travelling the next few weeks and DH will be at work all day. Right now the AC is on and is set at 74 degrees but the kitties are out in the breezeway (their choice - usually they love hanging out there irrespective of the temperature), where it must be about 78 degrees.

Our attic bedroom remains REALLY hot and we are scared to venture there in the summer months - we will need a window AC for that bedroom. The basement is cool - really comfortable and last summer we spent most of our times there and hardly ever put on the AC. The main level is moderate but the AC needs to be turned on to be comfortable. We cannot open the windows since flies have a way of coming in. We do not have ceiling fans. This is a rental and we do not plan to invest in these things. The reason I mentioned this is because the kitties have access to all three floors but not the breezeway when no one's home.

Would love to hear others' experiences with this and at what temperature do you set your thermostat.

I set my thermostat between 82 and 84 in the summer, and that's only if I'm not home and need to leave the windows shut. Otherwise, the A/C is off until it gets to about 95 on a humid day.

I have a sun room that has neither heat nor A/C. My cats choose to hang out in that room all year long, so I know they are fine with temperatures close to freezing and over 100. That room gets incredibly hot in the summer (south facing with a wall of windows).

I believe in conserving energy when I can. The cats are fine with it.

I have a real hard time with the humidity here in Chicago. I keep my thermostat at 75 degrees. If it gets above about 82 degrees outside, I start complaining . I am swedish and hot-blooded, would be just fine living farther north, like Canada . My cats seem just content with that temp. too. I also have to keep it quite cool in the house right now because I have an older dog with cushing's and is internally hot and needs to be kept very cool. So whatever Wilbur needs, Wilbur gets