You should only need a bottle of gas. Though you’ll need to check which regulator the Koda comes with. It’ll probably be clip on, rather than screw on.
I have a Koda (not the big one) comes with the oven, stone base for cooking on, gas hose and regulator.
You need to get a gas bottle (propane, look for Patio Gas with a 27mm clip on regulator configuration) and a peel to get the pizza in the oven (and out again)
I've found a German webshop stocking a Koda, so I've ordered that. They weren't very clear on what's included, will I only need to get a gas bottle?