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.
When your spreadsheet start to hit its limits, what options are open to you? Perhaps the best option is to consider the conversion of your spreadsheet to a database solution. Relational databases became viable not too long after the spreadsheet was well-entrenched as the affordable and quick means of gathering data and performing calculations.
You may also want to track your current spending on one sheet with columns for different categories. Some individuals will list the budgeted amount in one column and then list the actual amount spent in the column next to it.
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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