I have a product that I sell (a service actually) and I often ask for 50% of the charge up front.  I have Zoho CRM and Zoho Books...how can I send the customer an invoice for that 50% payment that they made when the only way to generate an invoice in Zoho Books is to change the entire Potential to "Closed Won"....the Potential is not yet closed since I am performing the work, so I would not like it to be closed, but I would like to send them an invoice for their partial payment.

Thanks!