One user at a time : In the instance where there are a number of people required to work on a spreadsheet, they can only access it when no-one else is working on it.
The mentioned package includes valuable programmed spreadsheets such as the "Income and Residual Tracker" - provides professionals in the entertainment branch with detailed information regular and residual income; "The Biorhythm Plotter" - helps users in planning various events and actions based on Primary and Secondary Biorhythms (the spreadsheet solution allows users to choose the right timing for their actions according to personal intellectual, psychological and physiological factors); "Basic Actor Package" - designed to facilitate the process of calculating expenses.
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.
Protection of formulae : How often have you forgotten to protect the cell contains the formula that took you hours to test and perfect. It takes one instance of honest human error, and that formula is gone.
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