I'm going to speak heresy, I say you get an electric smoker. Hear me out.
I've been using a Weber Smokey Mountain for years. It's great, but:
1.) I'm going to move soon, and likely have to go to an apartment where charcoal/propane is a no no.
2.) It's a pain to add more coals to the bottom of a WSM, if you're planning on cooking 16+ hours.
3.) It's a pain to control the heat just right, 10+ hours in. I often finish in the oven, so I can control the heat better.
4.) For butts, I don't think you want to smoke it more than 6 hours. Cook it low and slow longer, yes, actual smoke, no. Otherwise, smoke can taint the meat a bit. So, if you are only smoking for a small portion of the time you are cooking the meat, why does the type of smoker matter? It doesn't.
5.) Electric smokers can control temp better, and add smoke just as well. Yeah, without charcoal, you don't get a smoke ring. But that doesn't actually do anything to the flavor of the meat, and you can still get a smoke ring with a electric smoker, apparently, by throwing a few pieces of charcoal in with the smoke box.
For those reasons, I would go with the Smokin' Tex.
https://www.smokintex.com/