Something to remember about tanks and reels: If you buy decent ones, and take care of them, they can be the beginning of a collection...
Personally I've been using the Paterson tanks with plastic reels, simply because that is what was cheap and readily available to me when I first bought into a system. I started with the smaller "2 reel" tank, which fit one reel of the 120 film I was using. (Which since they also did 220 film, it means you can actually fit two rolls of 120 film on a single reel by loading them one after another. It is however, 'tricky' and easy to mess up if you accidentally overlap the film.)
From there I quickly added a larger tank, so I could do two reels of 120 film at a time. And that size tank also just happens to fit 4x5 film...
It also happens that I ended up with measuring cups that hold just enough chemistry to cover the two 120 reels, which is handy, and have since added a second large tank as well with a Mod45. [But am really considering switching my 4x5 development to SP-445 tanks] And I am in need of picking up more reels at some point...
Also debating if I want to have even bigger tanks! Because I have found myself doing more film work and getting larger back logs of film in need of development... But I'm very much on the fence as I'm not sure how clearly I could handle pouring that much chemistry in and out. [Maybe just more 2-reel tanks so I can prep them and run more developments back-to-back? ... ]
But TLDR - Tank collections grow as you find your stride, and compared to the film you can run through them they aren't badly priced. Focus on buying well reviewed gear, and don't let yourself get suckered into paying extra for random "Collectible" parts if you have no good reason for wanting them besides what an ad tried to tell you.