How can I create a retainer invoice automatically?

How can I create a retainer invoice automatically?

Hi Guys, 
We use Zoho one application and here is what I am trying to achieve.

We have lead modules in Zoho CRM, and we use blueprint features. I am trying to add a button with the help of the blueprint feature and the button would be "Send retainer invoice".

Whenever we hit that button, I want to send a retainer invoice to my lead. Is it possible to automatically create a retainer invoice and send it to my Zoho CRM record? 

Any help would be appreciated!

Thank you