Advertising material as a cost category for services or create a new one with the type of goods?

Goods in that context is a bit misleading; it actually refers to trade goods.

If it is not a trade good (i.e. 'Goods'), then it is either a 'service' or an 'investment'. So your advertising material is actually a service.

It's very confusing, and I've already let Dexxter know. In a new version, they will no longer show it that way because they acknowledge the confusion.

But yes, advertising material is only listed under 'Marketing & advertising of all kinds', which is fine.

Thank you for the clarification. It is indeed very confusing. Because according to what I read in the inventory, your printed matter counts towards your stock of goods. This also includes stickers that you do not sell but stick on every package and packaging material, all of which is advertising material. Services cannot be included in the inventory, only goods. Hence the additional confusion.

Printed matter that you are going to sell is trade goods.

But printed matter for advertising is not trade goods.