a few years ago i created a homemade security camera system using motion on my linux desktop and all of my unused smartphones as cameras with ip camera software along with the gnome google drive desktop plugin to upload pics/vids of events and notify me via email & priority phone notifications if something happened.
it was easy to setup, but it took forever to tweak the cameras’ angles, mask and especially the lighting with infra red light bulbs so that they could get decent light in the videos and pics during night time and without having to keep all the regular lights on all the time.
i’m glad that i didn’t spend any money of it because i only ended up with hundreds of hours videos and gigabytes of pics of me and my pets. lol