this is a huge topic, I find Reolink a good balance of cost/performance but their ONVIF support is not great. You will need to research each individual camera to see if it will work. Otherwise AXIS/BOSH, or get Chinese cameras and make sure they dont have a way to call home. If you go Chinese Dahua and Hikvision.
Get POE cameras!
NO wifi, WIFI is crap for cameras as they need a constant stream of video to be recorded. If they only write a file when triggered it means you will miss lots of events. Most NVR software, even FOSS records constantly but overwrites files until an event is triggered and then it locks the previous 10 seconds until the event ends.
Any non “consumer” solution should record to local storage. Consumer solution like Ring/Arlo are all built around subscriptions.
Frigate/Shinobi are decent NVR FOSS solutions, and any ONVIF compatible camera should work fine with FOSS.
again Frigate/Shinobi, and I think frigate even has HASS integration.
most good quality professional cameras have built in tracking, detection, and other neat tools. But in addition Frigate has more features you can apply on top of the built in ones. 2 way audio IDK about never looked into it.