CRM estimates not showing option for retainer fee

CRM estimates not showing option for retainer fee

I have enabled Zoho financial in the CRM so I am able to make estimates directly from my Accounts under the heading Zoho Financial. 

zoho crm with module finance integrated


But when I create an estimate I need it with the option to add the retainer fee which is present  in Zoho Books estimates.
Zoho books option create a retainer invoice to this estimate automatically

Where is the option to create an estimate within CRM and add the retainer fee option without having to transfer back to Zoho Books?
create estimate from the finance module in Crm no options to create ratiner fee invoice