Hi Sail! Welcome to the forum, and I'm glad to hear you've decided to take the plunge.
When it comes to guidance or any "gotchas", as you put them, they are detailed in the installation guide. One such consideration to make, for example, is to ensure that you get a device that is not carrier locked, as you then won't be able to enable OEM unlocking, and therefore will be unable to install an alternative OS.
When it comes to the actual installation process, all of the prerequisites and edge cases are detailed in the guide but you are encouraged to join our Matrix chat rooms and seek help if you feel you need it. Someone is usually around and we're quite happy to walk you through the process. :)
If you have any specific questions or concerns before more, feel free to let us know and we can try to tackle those for you.