When a floor plan unit is sold on a unit deal any floor plan interest that was accrued against the unit (included in its inventory valuation) will also be included in the costing/profitability of the unit on the customer order.
Any floor plan interest that was just "expensed" is not accrued against the unit (excluded inventory valuation) and therefore is not included in the costing/profitability of the unit on the customer order.
When the costing/profitability of a unit is recorded on a deal unit the unit cost used for this is:
Total Base Unit Cost + Total Factory Option Costs + Total Dealer Installed Option Costs + Floor Plan Interest Accrued
Floor Plan Interest Expensed on the unit is not included.