For working in Rental App is possible to add Items as rent item, which you have in storages. Not all of them are intended for rent and thats the reason why you have ability to create Item before creating Rent Item. For more information about creating Rent Item, see How to create Rent Item.
Go to Search and enter Items.
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Then you will see the list of all created Items. After clicking on button New you will see Item Card, which serves to register important item parameters.
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You can set up Inventory, Costs and posting, Prices and Sales, Replenishment, Planning, Item Tracking and Warehouse by your conditions.
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Field Max. Rent Item Count represents maximum count of this item that can be added to Rental App as rent item.
Note:
In case you want to rent this item, the field Rent Item situated in section Inventory must be turned on. If it's turned off, the Item can not be rented! In case when Rent Item Created is turned on, it means that rent item is already created from this item.