+ You can add items directly to the ah sell menu (this means if you run /ah sell without holding an item, it will let you place the item you wish to sell in the sell slot) this is enabled by default, but if you wish to force the player to hold an item to use the sell menu, you can change it within the sell menu.
https://gyazo.com/ef02a21a718e047638753d1538df2e93