At present, some of the most requested types of spreadsheet packages in the market are: 'Spreadsheets for Small Businesses' and a subset of that: 'Spreadsheets for Actors'.
You could make money doing something you love (or like [or maybe not so much but just really good at]). It's great to see a spreadsheet come together, and usually a lot better than what you originally envisioned. Especially when the dang thing works.
Undoubtedly, spreadsheets can help you improve the efficiency of your company regardless of the nature or size of your business. However, it is very important to note that the process of programming formulae and mathematical algorithms behind spreadsheet programs can be very complex and time consuming; one having to invest much effort to create the most appropriate spreadsheet solution for one's company.
You may want to create a workbook with multiple sheets for various aspects of your budget. You can have one sheet that keeps track of savings and investments and another sheet that lists your monthly bills.
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