Just to clarify for Earl (I know Ken and I have discussed this in the path and we don't have the same opinion here

), my comment was not meaning that you add a folder with name of the vendor who is creating the product, but to place product add-ons is under the same folder where the original creator of the figure put their figure and its addons. Some vendors also like to add their personal name folder below that.
For example, if a Joe MyName created a house and put it under
Runtime\Libraries\Character\Joe MyName\The Great House\
and I was creating free or for-sale furniture meant specifically for that house, I would put it here:
Runtime\Libraries\Character\Joe MyName\The Great House\Furniture\
Personally, I move all my products around anyway and sort them, as I said, but I like to know who created it.

So after I download, I'd change the folders to something like this:
Runtime\Libraries\Character\Buildings\Houses\GreatHouse_Joe MyName\Furniture_Alisa\
And then, I'd take the materials out of the material folder and stick them in subfolders.