a nice solution would be a "vote" system . when enough peoples (300-400) have blacklister somone (shouter or /tell bots) this account get a temporary ban untill a GM get in the case and check if this Worth a perma-ban or an simple warning , that way the whole communauty participate to the effort against RMT

honestly , you blacklist them anyway , might as well use that fonction to help everyone , you blacklist=you vote . easy and simple