What are you trying to achieve? The UClass* of a class can simply be retrieved via GetClass() if that is what you are searching for. If you filled your actorType with that in the constructor of AInventoryActor every class inheriting it’s constructor would set it to it’s respective class. But why would you need that anyway? You can just use GetClass() on the instance when needed, no need to store it anywhere.
Except if by: “would like to set it to whatever class is currently the child of AInventoryActor” you mean somehow getting the class of a subclass, which I don’t think is possible.