I have seen people around the web are using these cameras with espHome and creating diy doorbells. Anyone doing it here, if so how well do they work?
Another link:
You could do this as well with zoneminder and a generic camera.
You can’t do it for as little as $9.
But yes you could with zoneminder chewing CPU power to create a movement alarm which would not be as good as a PIR against false alarms. This solution can do the PIR sensor in the esp32 hardware freeing up the power of your server for other things and not needing another software package to learn or maintain. Opensource firmwares for cheap esp based hardware is now here.
$9 to buy a basic esp32-cam
$19 to buy the model linked above which has the PIR and OLED screen
You’re right I couldn’t do it for $9 I can do it for free. Already have a zoneminder server with 15 cameras and I get cameras for free 
On a side note, zoneminder could be nearly 100% accurate with very few false alarms.
Your my new best friend. PS do your friends get free cameras ? 
Will have to check Zoneminder and also the Motion project out one day as they have advantages (as well as disadvantages like heat and cost of server) for sure especially when you have 15 cameras.
New video showing the camera off…
@Jarred_Youngblood , I have a small ZM setup integrated into my HTPC, but the CPU consumption is too much for the cameras I need to add. I’m going to have to build a dedicated ZM server (looking at, ultimately, 24 cameras). Assuming 720p average and 6 fps, do you have some thoughts on some appropriate hardware? I have several buildings and areas to monitor, but I prefer to keep to DIY builds on Linux whenever possible…
I have over 10 camera’s all 720p or higher with 24fps min, some have night vision and/or IR sensors for night. I’m using an Ryzen 7 1800, on average my core usage is 3-4. Runs 24/7.
Sorry for the delay in response, didn’t see the notification.