Question about selling Mog Station items

[MomomiMomi]

So, I see people post in the PF now and then, that they are selling items from the Mog Station. I wanted to know how this even works.

Are some items tradable in game or is this a system of trust between players, where they just have to hope that the seller gifts them the item after trading the gil over? (I have seen this done many times in other games and usually there are very few hiccups, but I just was curious how it worked here.)

Thank you for your time. ^^

To my knowledge, this is against the ToS. (though I disagree that it should be.)