As Matthew said you buy enough stuff at once to get free shipping. So multiple carb kits, multiple spark plugs, throttle cables, sprockets, and chains. Not all tracks sell the carb kits, but other things they may. It all depends on the track.
When you’re learning, you may go through more items than you will once you’ve become comfortable driving.
I’ve been running the KA with my daughter for about 5 years now, so feel free to DM me with questions on what I’ve spent and what not in regards to the KA.