So, I'm not on d2jsp very often but my brother uses it A LOT for Diablo II. I really like how easy it is to buy and sell items and the large number of users really helps to find what you need. The reason I made this post is because I recently started playing Nexon's new game Dungeon Fighter Online. It's really fun and I like it a lot but the main problem I find is that there are so many different items and it's hard to find someone who is willing to buy what you have, unless you pay cash for a merchant stall and afk in the trade channel. Another big problem is that it's hard for some players to afford items from other players due to high prices, this leads many players to resort to spending real money to buy gold from gold and powerleveling websites. d2jsp could fix both of these problems by adding a Dungeon Fighter Online forum because no only will it make it much easier to find a buyer or a seller for your items but you also have the option of using forum gold to purchase your items eliminating the need to spend hours farming (if you already have some fg from another game or donate).
There is at least one forum that I know of that has a DFO marketplace, but it isn't very well organized in my opinion and because it is just a regular forum without any special formatting, it is still hard to search for items that you are looking for.