Grill, charcoal basket are good choices.
I keep mine outdoors, I use a cover.
5 Observations:
Kamados come ready to cook. You don't need accessories. The charcoal basket and a deflector/drip pan are first choices. The rest depend on where you want to go with your cooking .
Choice of kamado. They are more alike than not. No kamado envy here. Get what you can afford and is available.
Lump, more alike than not. You put it in and light it, it burns. Some are hotter, some have bigger pieces, some people detect different smoke flavor. It all works.
Wood chunks/smoke...Less is more. Keep in mind the folks you are cooking for. Don't over smoke.
Grate vs dome temp. Does not make much difference as long as the dome thermometer is reasonably calibrated. I am pretty sure I could cook anything without a thermometer measuring grill temp. Comes with experience. Temp control device....I bought one, but I can use the kamado sans device. Certainly not a necessity for searing a burger.