An invoice is also issued in the rental industry, where the duration of the rental being billed is specified.  The rental invoice will include quantity, duration, price and discount.  In most cases, the document will specify hours, days or weeks of rental with the equivalent price.

The invoice is regarded by the seller as the sales invoice, while the buyer think of it as the purchase invoice.  The written document contains the name of the seller and buyer but in actuality, the term invoice means the buyer owes the seller. 

commercial invoice template