I have a temp controlled kettle that only cost like $40, some really nice french presses from thrift stores, and a couple really nice pots ranging from iron to ceramic but they were a one time cost about 10 years ago.
You can cold brew tea in a big mason jar and strain with a dollar store strainer even.
The scale for weighing was expensive but is super useful in a kitchen anyways.
So the expensive part of Tea is mostly just the tea but that varies all over and is down to taste preferences and marketing. And per glass is pretty negligible in cost. As long as you aren’t buying like the aged fermented monkey picked stuff.
Tea is a lot about patience and remembering organization of steps to get it perfect and that can be prohibitive but not cost if you don’t want it to be.