Programmable thermostats

One of the smartest things I did as an Airbnb host was to have a programmable thermostat installed. And not just any kind of programmable thermostat either.  First, it needs to be one that will allow you to set high and low temperature limits.  What does that mean?  It means that guests can't turn the heating above or the cooling below the limits you set. Second, you should be able to lock it using a PIN/password. This is sometimes known as a landlord's thermostat.

A regular old thermostat like this will
wind up costing you lots of money

A thermostat like this doesn't need to be expensive.  I chose a Robert Shaw model that cost less than $100. Of course, the one you choose will depend on your heating/cooling set up so check with you HVAC contractor if you're not sure.

Ok, so why do you need this? Do I really have to explain it?  Because without it guests will turn the heat up or the air conditioning down as far as it will go. And leave it there.  Even while they're out all day.  Not all guests, mind you, but enough to cost you plenty. Your current thermostat lets you set the heat as high as 90F (30C)?  Then some guest will set it there.

Before switching, the worst problems I had were with Brits who set the air conditioning to 59F (15C).  One didn't bother closing the windows either.  So while a programmable thermostat won't solve the window issue, it will at least help rein in guests and help keep your utility bills under control.