You'll need to develop good marketing material. Things like demo videos, which you can find plenty examples on YouTube, screenshots, and keyword rich descriptive text help people find your spreadsheet and communicate the value that sets yours a level above the rest. Excelville.com actually allows you to upload your spreadsheet with all of this marketing material in an easily searchable and user friendly website.
However, companies can nowadays achieve these goals with less effort and in a cheaper way by using properly designed spreadsheets. The right spreadsheet solutions allow companies of all shapes and sizes to achieve and maintain a prominent position on the market, optimizing and accelerating a wide range of specific business processes and tasks.
You can build a reputation as an expert spreadsheet developer. This certainly doesn't hurt the resume. Using Excelville.com to sell spreadsheets allows you to set up a profile with your work, biography, and other info that certainly makes for good conversation material during interviews.
Once you design the type of budgeting spreadsheets you want to use, it will be easy to copy it for subsequent months or years. You can also use just one sheet and create tabs for each month.
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