I know about all of those merit abusing things. The first thing to do is to report to moderator. This thread is also good way for true searching, but you must to represent proves. For now it's only saying.
How can you report to moderator of the Merit is being sold outside the forum? I have seen this kind of offers as well in Facebook groups that is related in cryptocurrencies. Its hard to catch them because if its being sold outside the forum, you can't tell what username is being used by the seller unless someone is willing to go undercover and play as a buyer. But I think if there would be a penalty to merit seller, merit buyer should be treated the same way too.