Which of the following is most appropriate for a "Cash with Order" terms of sale?

"Cash with order" is a term of sale in which a buyer must pay for goods at the same time as placing the order, before the seller dispatches anything. Because payment happens before any goods move, the seller needs a document that quotes the price and terms of the goods so the buyer knows exactly what to pay, without that document being a demand for money already owed.

A document that lists the goods, their prices, and the terms of the intended sale, sent to a buyer before an actual transaction is concluded, is a proforma invoice. It allows the buyer to see the cost, agree to it, and send payment along with the order, which fits the cash-with-order arrangement.

A debit note and a credit note are both used after a sale has already been made, to correct undercharges or overcharges on an invoice already issued. A consignment note is a transport document that accompanies goods sent to an agent for sale on the owner's behalf, and it has nothing to do with upfront payment. None of these fits a situation where money must be sent before the goods are even ordered in the seller's records.

When you see "before the sale is finalised" in a commerce question about documents, think proforma invoice; once the sale is done, the relevant documents become invoices, debit notes, or credit notes.