Agile Budgeting for my Products

This is a version of my product portfolio management and how I am safeguarding funding in all the products and products pipeline.

I am employing the Agile Budgeting approach to invest in these products.

I have 2 books which I am considering my products in the market and another one is in construction.

The Agilist Guidebook, which is in the market from 2018.

The Scrum Master Guidebook, which is the market from 2019.

The question is, as I can not afford for annual budgeting for these products, how can I continue to invest resources into these flow?

What I am experimenting with and trying to improve is below 

Each product I have multiple EPICs to push to the productions.

Each book takes 1-year cycle time to reach production and after production promotional exercises.

Every product will go through is product development life-cycle before it progresses to its natural death.

I have practically 4 EPICs, each considering three months cycle time to accomplish.

The Agilist Guidebook has 4 EPICs. Each EPIC has a benefit hypothesis mentioned and connected Lean Business Case hooked up to the EPIC. Before books go to the market incrementally, I am spending time and money to each EPIC and validating my learning.

I have a portfolio backlog, which has all these EPICs now.

I have the 3 Value streamline, One for The Agilist Guidebook, One for The Scrum Master Guidebook and Another One for The Guidebook for Personal Leadership & Self coaching.

Each EPIC reflects the Lean startup model.

Some MVP hypotheses I add into each EPIC and this cycle goes on.

I include leading indicators to conclude if I should scale up or pivot.

Most of the KPIs are the number of books sold, Reader satisfaction information I collect.

Mostly the Traction data of these books guide me to organize my resource( Time and Money).

I have a portfolio Kanban board to oversee the product development FLOW.

How am I spending? 

I am applying Agile Budgeting for these books. I cannot afford the annual budget cycle. I have to extremely conscientious about my money and time(both are restricted for everybody).

Some money I kept for The Agilist Guidebook (10% of my time and money)

Some money I kept for The Scrum Master Guidebook (30%-40% of my time and money)

Some money I kept for the new book which is coming, The Guidebook for Personal Leadership & Self coaching., (50%-60% of my time and money). This is a research project for me. The EPIC Hypothesis and Lean Business Model instruct me to invest on EPIC or Pivot some of the hypotheses.

Based on the decision Go-No Go cycle, I can organize my resources to another value stream if traction is good.

Every quarter I have analyzed with a few team members, how I am proceeding against these hypotheses. A few of my colleagues helped me to validate those with data and judgments.

Though I do not have many individuals to handle all these, it is my publisher and a few of my trusted companions to drive the whole show.

Do you find these similar in which we work out the same in Organization esp in SAFe Lean Portfolio Management is all about these? Mine one is a very modest product portfolio.