If you want to buy 400 items of same type, it's worth considering contacting some seller who's going to sell you that amount of items.
Just keep in mind that I'm only going to consider adding features that the majority of players can use, ability to buy dozens of items at once doesn't fall into that category.


Also some stuff I haven't announced here, there's been a few updates this Monday:

• Fixed bug with purchase potentially getting you a different item (same itemid and price, different inventid) than you originally wanted
• "Search in market" button in website inventory now opens item page in new market
• "Market items" button in shop shell now opens your market shop page
• Ability to set price for item from website inventory has been removed
• Market inventory has been removed from website inventory type dropdown

All items that you still had in the old market are currently still marked as "on sale" in the system - this is done so you can quickly migrate them to new market from your Marketplace shop page.
Any items not migrated by December 1st, 2021 will be put in your deactivated inventory.