Hi there! can anyone help me on this? What I want is we will offer an incentive to the customer to buy us a machine by offering him a $5,000 voucher to be used for other products. I need to create a link so that the buying of other products with the $5,000 voucher is linked back to that customers proposal and not seen as a separate transaction. How will I do this? Is it discount coupon or gift certificate?

Thanks!