Some basic questions about Kodi Hardware

I just discovered this forum and am a little confused about some things. First, let me say I have been using Kodi for several months on a Fire Stick as someone introduced me to it. I like it for the video library to watch DVD’s I burned to a hard drive and also some of the add ons (I travel a lot so it is great to pick up some of the networks, You Tube, etc.) Anyways, I want to get something a little more permanent and with more power than the Fire Stick as it does seem slow or laggy at times. I have been looking through this forum and don’t really know which route to go. I see several Android boxes for sale that I imagine would be easy to install Kodi from the Google Play store. Then I see something about LibreELEC being installed on one of these boxes. I read about Rasperry Pi and found some small kits for those on Amazon. I see a Fire TV Box also might work well. So what is the best route to go? I know the answer is going to be “it depends” but maybe I can help narrow it down. To start with, I would like to keep this around or under $100. I am getting pretty familiar with Kodi and enjoy changing skins, customizing it, etc. so I don’t know if Kodi is the same or not on all platforms, but I am familiar with the Android version since I am using it on a Fire Stick, so it would be nice to not have to learn something totally new (I imagine Kodi is Kodi on whatever you use it on though, right?). I can also run this wired as I have ethernet ports throughout the house. So what is a good route to go with this? I guess I really only need the box to run Kodi, as if I want to use Netflix or Amazon, I just use the apps on my TV. It would even be cool if it just booted right to Kodi as it would be easier for my wife to use it. I have Firestarter now but for some reason it doesn’t always boot directly even though I have it set that way. Thanks in advance.