If I upload a FBX into the marktplace, Is it necessary, that the file is avaible still on the original position?
Yes because you dont actually upload the FBX, you upload the FST which points to the server where your FBX model is hosted, and that is where the users get it from.
If you remove the model from the original host it will fail for everyone who has the object.
I really am not sure how this will play out in the long run, when people start providing stuff then simply give up, those who have received the items will end up with nothing.
That will be a bit odd… i buy something in Marketplace, 2 weeks later creator deletes him, he left HR or he dies… so, me and everyone will loose Money and the Product. That isnt good to create a trusted martket in HF
Well, I think it is only a first possibility, to start with a marktplace. Wait and see.