Product name: project name/product name
Certificate number: certificate number
model
Price: List price
Actual selling price: selling price
Cashier: Cashier
Seller: manufacturer/distributor
The "selling price" should be the price listed on the quotation, that is, the list price. "Actual selling price" is the actual selling price, that is, the selling price or the actual price.
"Seller" is called producer in American English, which is equivalent to Sales Rep, and seller can also be used. If it means "distributor", use distributor or distributor.