So you can buy a DVR/NVR (e.g. one from Reolink). That looks like a dvd player, the cameras connect to it and it records all the footage depending on how you set it up. If you have POE cameras, get a POE NVR and it will supply power to the cameras over the network cable as well.
OR, use a PC with Blue Iris (or any other NVR software) to do the same function as a dedicated NVR. I am going to get a surveillance HDD for my PC to record on. You can view this footage from any device on your network or even outside if you set it up that way. Advantage is you can use an AI tool like
@alqassam mentioned, which scans still images from the feed when motion is detected. It figures out if it is a tree/person/car/whatever and you can get alerts based on that. There is also a face recognition module, not sure how well it works.
This is still theory for me as well though, my cameras should be delivered next week then I will see how it goes.
If you buy the RLC-410's, POE is definitely the way to go to simplify cabling and routing. You can buy a 4 port Tenda POE switch from Scoop for around R500. This has a power supply and connects to your home network. The POE ports take a LAN cable to each camera that supplies power and data. You can then detect each camera from anywhere in your network, either on your pc on NVR.