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.
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.
The templates designed to use for saving calculations varies according to the saving calculations made depending on the types of calculations to be made. These spreadsheets make the calculations and the data entry easier than doing it by any other format.
Elaborate, properly constructed spreadsheets greatly simplify a wide range of activities and processes within companies, enabling business owners to economize valuable time and effort, increase the efficiency of their business (Analysis), keep track of different tasks, manage their budget, optimize the planning of future events (Forecasting), organize and access valuable information, and optimize the completion of specific tasks. And thus, thanks to their many benefits, spreadsheet programs have come to be considered indispensable tools for businesses in today's competitive climate.