Do you want instant response to a situation, or the (posted) promise of a thorough followup to any incident? Remember, when seconds count, the police are only minutes away.
As a secondary security system, you might want one which cannot easily be hacked, so that eliminates wireless. The (preferably) digital recorder should be inside a very heavy duty safe, protected against fire and humidity and bolted to the concrete floor, along with all your other 'valuables' inside. Cameras, wiring and power sources are secondary in your consideration, as to whether they are subject to darkness, interruption, hacking, power outages, wiring interruptions, vandalism and such. Any alert alarm, inside or outside, needs to be inaccessible and 'louder than hell.' How much coverage do you need, how many locations, do you want color and good image quality? Do you want instant notification to you and/or authorities, or posted warnings advising quality recording and virtually guaranteeing prosecution and conviction after-the-fact, thus possibly resulting in prevention? Landline connection, (not as too easily intercepted, but subject to cutting), to notification of you/authorities, or (more hack-able) cellular notification? Then you want to consider quality/reliability/reputation of the company and its product.
Carry On!
Gary
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