I could tell you this much that my parents house has ALERTA and I've forgotten the password twice when I opened the door,and someone always showed up on a dirt bike fully armed,he asked me for the secret password that I didn't even know about,I had to call my aunt to tell me the pword they ask for if they see someone in the premisses.But they were responsive both times and besides I seen them circle around that urbanization before without alarms going off...and I invested in a rottweiler 2 years ago I keep at my abuelos house that I bring over when I stay..
i think companies like alerta are not cheap. but they work. it's more expensive that a guachiman but more reliable, better trained, better armed and there is a rotation of staff so you do not have to worry about holidays and such.
I could find out how much we pay for alerta, its not that much because we don't have cameras or internet acces to monitor it.they have a website
please do, that would be helpful. aC