There are several places to add discounts to a quotation. Click on the blue heading to expand the panel and then click 'new' to add your discount or deposit amount.
Primarily for any discount you have agreed (following feedback we chose to call it adjustments instead of discount!). Adjustments can be as a percentage or a numeric amount in pounds.
Add as many deposit lines as you wish. Apart from adding the customer's deposit here, you could also add a line for any dealer contribution or brand contribution too.
You could also add any over allowance given on a PX.
Note: You could add a Dealer contribution discount to the Dealer Options section. But this would be before VAT is calculated.