This is sort of a use-case question how to do something 'the odoo way'.
Sometimes a sales person gives a contact a 'commercial sample', of a stock product that has a certain value.
At the one hand you want to update the inventory that one item of that product is gone.
On the other hand you somehow want to keep track of how many products have been handed out, and their value, probably also in accounting.
What would be a good way to do this in Odoo ? Just create a sale order ?