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Hi, I have a CCTV surveillance system already a few years, but is incomplete, I have about 3 dome cameras and 4 more "normal". ( all VIDEOTRONIC Cameras ) I have little knowledge of CCTV systems, but I have good computer skills. Can you give me a hand? What i need to complete this system ? This system is worth its recuperation? Or is it preferable to a better investment? What brands recommend and what material recommend? Best Regards