Floor plan financing is a revolving line of credit that allows the borrower to obtain financing for retail goods. These loans are made against a specific piece of collateral (i.e. an auto, RV, manufactured home, etc.). When each piece of collateral is sold by the dealer, the loan advance against that piece of collateral is repaid.
In short, Dealer Floor Plan financing allows dealers to borrow against retail inventory. The dealer then repays that debt as they sell their inventory and borrows against the line of credit to add new inventory.