Back in the day i played with 16. Two computers.

Each pc had: i7 6core/12threads, 64 gb ram (you may go 32gb), 980ti 6gb vram, 650w powersupply, 250ish ssd, 2 x 24 inch monitors. 2 x 12cm aio.

It worked well i think.

Maybe you can find something similar or better (ideally) for a good second hand price.