You'll need to find a way to make your spreadsheet accessible. You can build a website, which will require paying for a domain, hosting, site security, dealing with an internet transaction service, graphic design, content for the website, marketing your website, Search Engine Optimization, and all the other madness that comes with managing a site.
Most spreadsheet applications have built in formulas and functions that will do the math for you so you don't have to. You can keep a running balance of your accounts and you can have each category totaled as well. You can keep it as simple or make it as sophisticated as you please.
You'll need to include more than a basic level of development and calculation in your spreadsheet. There are lots of free spreadsheets on the web. Most of which are very simple and easy to build. People aren't going to buy a spreadsheet that they can get for free. Take yours to the next level by adding all the value you can imagine. Then research on how you can offer a little bit more on the development and functionality side.
Spreadsheet applications are useful for home and small businesses. Some people keep a home inventory list on a spreadsheet and others use spreadsheets for a variety of applications. Creating your budget and maintaining it is easy when you use budgeting spreadsheets. These are also easy to print out if you desire.
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