reply to ImpldConsent
Re: What to leave on - empty house Thank you for your service!!!
Why bother with the A/C? There were houses long before we had A/C and they did fine. If you are really concerned, I'd imagine a dehumidifier draining to a sink would use a lot less electricity than an A/C.
Other than the advice of having someone checking on it and timers to make it look like someone is home. As well as a motion sensing fixture would be a good idea.