It's extremely easy to set up with docker, I've been using a self-hosted instance for about 2 years now. Contact me if you need help setting it up or if you just want to test it.
Hardware requirements depend on how many users will be using it, I use an old i3 NUC as a home server and it can easily handle a room with a dozen people, especially if it's just audio, it gets heavier on the CPU if a lot of them have their webcams on but generally speaking if you have a decent internet connection you'll be fine.
Follow these instructions: https://jitsi.github.io/handbook/docs/devops-guide/devops-guide-docker/ You will need to set up HTTPS unless you're already using a reverse proxy.