Would a Raspberry Pi Zero be sufficient to run motionEye? They are sufficiently cheap so that one camera could have one Raspberry Pi Zero attached to it.
I just wanted to add, while I have an Arlo Pro as well, I've found the Raspberry Pi Zero solution cheaper and more reliable. The Arlo's camera quality is better, but the software often fails to capture someone walking by. I'm also more skeptical about how safe my videos are on Arlo's servers.
I run it on a Raspberry Pi 4. No camera is directly connected to it. All cameras are WiFi based and it records 10 streams of 720p/15fps over RTSP.
motionEye can also be used directly on Raspberry Pi Zero along with the Raspberry Pi Camera but I don't use that setup as getting night vision to work on it a hassle and expensive, comparatively. It works though :).
This is what I used to set up a home surveillance with notification alerts.
https://www.bouvet.no/bouvet-deler/utbrudd/building-a-motion...
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I just wanted to add, while I have an Arlo Pro as well, I've found the Raspberry Pi Zero solution cheaper and more reliable. The Arlo's camera quality is better, but the software often fails to capture someone walking by. I'm also more skeptical about how safe my videos are on Arlo's servers.