I'm gonna go ahead and call you out on this. Nobody's making 800k in a day by selling MK-6 kits.

Even if you're getting your mats for free and selling these for 40k, you've got to be able to craft 200 items and 20 kits. Raw crafting time is about 5 hours. On top of that, you'd have to farm something like 4 mats per minute (and hope your REs give you good returns) over the course of that 5 hour marathon.

So ok, it's possible....but nobody's doing that!