Shed Burglar Alarm Recommendations Please

[aussiblue]

Recommendation for a good and super reliable shed alarm please. I have tried several versions of this generic sort of thing https://www.ebay.com.au/itm/wireless...wAAOSwVRpfDV1X over the last few months and something keeps triggering these alarms even if I am only using the magnet door switch and no motion sensors. It triggers randomly but usually within 20 minutes of arming (sometimes with 5 minutes). You would think that being in a colourbond shed and surrounded by metal on all sides would stop most external signals interfering with it. There is also nothing inside the shed that I suspect could be triggering it; nothing is powered on at the various mains power outlets. I have cameras that monitor the shed and a good padlock but there have been several attempts to break into it over the last year since the block behind me is being redeveloped and is essentially now a vacant block. Video footage is never sufficient to identify the hoody wearing scum attempting to break in. Fortunately, I am a very light sleeper and so far have disturbed the felons before they got past the padlock. This luck can’t last and it is also turning me into an insomniac laying half-awake listening for trespassers. Altronics, and Jaycar have surprisingly nothing suitable. I would prefer something that is mains powered with a battery backup that sets off an alarm when the sliding door is opened. I am not keen on motion sensors as there are too many critters such as geckos, skinks, juvenile dugites and likely mice (although I’ve seen none or any droppings) that move around and would set of the alarm. Is it worth spending $700 on one of these Yale systems from Bunnings: https://www.bunnings.com.au/yale-eas...m-kit_p0079199 or will I have the same issues? I would also be interested in any ideas on what might be triggering the alarms systems I have tried. All my vehicles have good and multiple security systems; this is more about securing my tools etc.