Making one with a Pi Zero W + the camera is pretty straightforward. Most of the good network cameras with simple APIs (RTSP or MJPEG) are not so trustworthy on the security side.
What camera?! Seriously though, I don't necessarily want to write device drivers for a camera, maybe it's time I start looking at usb webcams to use?
There are also a ton of different 3D-printable mounts and jigs for them on sites like thingiverse and instructables.
My favorite[1] comes as a kit with the jig, 3 servo motors, and an add-on board for a raspi. Using this I have a live-feed camera that can rotate up to 180 degress on 3 axis that I can control from anywhere in the world using my phone as long as my internet connection is up at home. All hosted locally, even the live feed frontend. It's not hard to build or set up either, took me a lazy day and I'm far from a good coder.
1: https://shop.pimoroni.com/collections/raspberry-pi/products/...
I remembered incorrectly, that PiMoroni kit does not include the 3 servo motors, you need to buy those separately along with the RPi camera module. Luckily the servos required are super common little blue servos that are all over eBay and such for dirt cheap.