Most people don't know this but you can get home security systems through ADT just like in the USA. They aren't too expensive. Obviously thieves could still break in but a blaring loud alarm scares them and they almost always leave immediately. I had this system installed in my office and it deterred them and they ran away without getting anything.
You can also install a security camera easily that will record things and email you it (Google Panasonic network camera). Although this is better if you suspect employees of stealing. The judicial system .doesn't work in Argentina so even if you get a photo/video of someone stealing I'm not sure they would do much with it. Although I did catch an employee once of stealing money on camera and got him to quit vs. having to pay him any severance. In true Argie fashion.... the employee, although we clearly could see he was stealing on the video tried to deny the incident!