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.
Selling spreadsheets helps you to build a catalog of spreadsheets that you can take with you and use in various areas of your life. Spreadsheets built for sale are usually built for flexibility and would be customizable to your life, or job, or new life, or new job.
Rather than having to go through the pain and suffering of learning a new technology and having to experience trial and error development, the best route would be to acquire the services of a consultant, who can identify your needs and create a customised solution. Obviously, the cost of such a project would depend on the size and complexity of the spreadsheet and your requirements. However, you might be surprised at how cost-effective this project would be.
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.
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