Awesome, happy you managed to find a solution and also appreciate the heads up about that brand, I'll look into them but will only purchase cameras that support RTSP or ONVIF. I'm horribly disappointed to find that my newly purchased EZVIZ camera (C8C) does not support this so I'll be returning...
I have the same problem. The native firmware that comes with these cheap cams does not support static IPs unfortunately. You can however (in theory) use what is known as, "DHCP Reservation" which assigns an IP to the MAC address of the device. This can be done from your routers' firmware. TPlink...