I have a Wyze cam that I installed OpenIPC on. Very simple process if you’ve ever flashed a firmware before. OpenIPC lets you turn off the cloud stuff and I have mine pushing video over my local network to MotionEye on a Raspberry Pi. The Wyze has IR night vision but the IR can’t see through windows at night so be aware of that.
It was like $25 on Amazon, pretty good deal I think.