Home Security/Alarm Systems

Due to our recent break in we are in the process of getting quotes for a home security system. Probably the worst week of the year to do it too!! DH wants it monitored and we will be paying outright for installation etc and not locked into a contract.

Whilst it all seems pretty straight forward, as we've never had one before, are there any hints or tips or things that we need to be aware of? That you may have discovered whilst getting your own? Or cropped up down the track that you wished you'd known when going through the purchasing/installation process? As I don't know what this might be I can't give examples of what I might mean lol

Thanks in advance :)