Kickstarter

For the ultimate in simplicity and control, many freelancers start with a well-designed spreadsheet template. Platforms like Google Sheets or Microsoft Excel offer free or low-cost templates that can handle income/expense tracking, invoicing, and profit calculations. This approach requires manual data entry and a basic understanding of spreadsheet formulas. While it lacks automation, bank feeds, and scalability, it's completely free, customizable, and keeps your data offline if desired.

It's a legitimate starting point for solopreneurs on an extreme budget, those with very simple finances, or who want to deeply understand their cash flow before investing in software.