So for the Leopold FC980C + Heavy 9 + JTK Zen Base, Extension, and white spacebars + Deskeys Sliders… ugh, a lot
However, I have good news if you’re asking about the Bluetooth Controller: it was around $70. But it was from Taobao, so if you’re not in Mainland China, you need to get it shipped through a proxy service which will add expense. Here’s a related thread: