Also consider the Lissen app for audiobookshelf on F-Droid. I’ve been using it and find it to be a much more enjoyable experience

For whole-home audio, be sure to look at Lyrion! Formerly Logitech Media Server, it’s now a community-managed project. It’s easily the best open-source whole-home audio solution out there

lyrion.org

I’m using them inside. I record to microsd on each camera, and use homeassistant to view them. I’m eventually going to build a NVR for them

I’m using Reolink E1 Zoom cameras. My router’s firewall keeps them offline, and I manage everything through HomeAssistant. Very happy with my experience on a budget

PiCorePlayer and LMS are the way.