Appliances stolen from house on market

We just had our appliances stolen from one of our flip homes that we have for sale. We are diligent at keeping the doors locked and only have one lock box with a key to front door only for realtors. We do not have a security system/alarms set up. The last person there was a realtor with a client for a showing. My question: how many of you install WiFi/ security system and or cameras for your flips? Have you ever heard of people who schedule a showIng to purposely leave door unlocked