Bring two locks when you travel
I've always been paranoid about leaving valuables in hotel rooms / AirBnB's. To ease my mind, I travel with two locks. One to keep my bag shut and another to secure my bag to something stationary like a bed frame or set of drawers. The hope is that these simple countermeasures make stealing my stuff unappealing, especially when the would-be thief doesn't know what's in my bag. And if something is valuable enough that I'm uncomfortable leaving it unattended, then I carry it with me.
This cost-effective solution prevents you from having to deal with scrambling to recover / replace your things in an unfamiliar environment when it's least convenient. Of course, anyone with enough determination to steal my things will find a way. But, this makes it difficult enough that it'd need to be premeditated, which I assume is highly unlikely.