The Retainer Invoices and Packing Slip Templates are way too limited with zoho's default options for customization. They should have the same flexibility for customization as the Sales Orders, Estimates, and Invoices do, allowing complete control to add html to customize the look, feel and company specific content. The retainer invoice has the smallest credit card icon when payments are enabled. There is no way to draw attention to or highlight the payment area or link. Our customers are not seeing this icon and thus, do not know how to make a payment to us even with the very small text instruction. This slows down process efficiencies. There needs to be away to add a custom image or icon that is much larger and highlight or draw attention to the payment area. If you are going to give the ability to add text there which currently exists, at the very least the text should be clickable with the same payment url at least then it could appear as a link. Also, that font size cannot be changed however you give the ability to change the font size of the Notes (above it) and Terms & Conditions (below it), this in my opinion makes no sense.