To link an Existing Item to an Item Occurrence located within a Room, you need to identify the individual Item within the Item List for the : 

• In the Rooms Module open the Room to which the Existing Item

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•  is to be transferred and locate the individual Item Occurrence within the relevant Item List.

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This will then register append any data information associated to with the Existing Item to the Item Occurrence located in the Room (ref. /wiki/spaces/DFW/pages/1125611473). As Existing Items are allocated to ItemsItem Occurrences the total net quantity for the Item will be accordingly reduced and the Gross Quantity represents the sum quantity of existing and new.

Note: The software does not prevent you from registering an excess amount of Existing Items for an Item, so you have to take care that the net quantity is not negative.

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Once you have linked Existing Item to an occurrence of an Item in a room, you will no longer be able to delete the Item from the room without first removing the association with the Existing Items. If the Room has been populated with Items from a Room Template or Template, you will not be able to change these until any Existing Items have been removed from the Rooms which utilize this list. Consequently, you cannot delete or redo the list until this has been done.

Linking Existing Items to occurrences of Items in Rooms

Firstly if there are multiple instances of the Item then they should be split into individual occurrences (see below):

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A "Select Occurrence" panel will appear and allow you to allocate the Existing Item.

Linking Existing Items to occurrences of Items in Rooms (Method 2)

There is another workflow that can be utilized within the Items Module for linking Existing Items to Items in Rooms:

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