How can I build a better client-facing tool for delivering quarterly estimated tax payments (similar to SafeSend)?

A member described starting work on a tool to better deliver quarterly estimated tax payments to clients, inspired by prior session demos. They asked Claude in chat to build something similar to SafeSend, which produced an HTML-based deliverable that looked polished. Their approach was to start by designing the client-facing deliverable and work backward from there, but the discussion was cut off before a full solution or outcome was described.