House flipping is already a bannable offence, and SE has already put measures in place to stop it happening (such as a randomised timer for the plot being reopened), its been this way for a while now. It's nowhere near as big a problem as it used to be. If you see a player like that, report them. Otherwise you are judging a player on a percieved assumption of wrongdoing.
https://forum.square-enix.com/ffxiv/...to-this-thread