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 budget spreadsheets are little more advanced than the other as they have to undergo higher and tougher calculations and data entries. The budget planners vary according to the particular budgets. These templates are designed such that it fits the particular budget whether it is a wedding budget or the annual get together budget.
Spreadsheet templates are used for many reasons and each template vary according to the purpose it is used for. Spreadsheets are designed with different calculations depending on various needs.
spreadsheet templates for business
spreadsheet templates for tracking