Existing or transferable Items can be imported or entered into a dedicated register in dRofus.
These Existing Items can then be associated to planned Items within Rooms.
Typically, you might first register all Existing Items which are to be relocated, then later decide whether the Existing Items can be used to represent Occurrences of Items in the Project.
A selection of Existing Items can be linked with an Item and then, as the next step, individual Existing Items from the selection can then be associated with Occurrences of the Items within Rooms.