What is Quick Sale?

Quick Sale is an order that acts as an Invoice and also a receipt of payment at the same time. It confirms the quantity and price of items/services sold, removes them from inventory, and receives payment. Use Quick Sale when the customer is paying for and picking up the items/services at the time of purchase.

Quote/Estimate vs. Sales Order vs. Invoice and Quick Sale

http://help.zarmoney.com/en/articles/1452565-quote-estimate-vs-sales-order-vs-invoice-and-quick-sale