You may think modeling an item price will be too hard for you. I will show you how to do this and you can apply it to any item regardless of type.
Item price = rate x quantity
Sounds simple. If the rate is fixed and the quantity known, it is simple. We store the item definition about rate and quantity. These parameters will be used as the base parameters for computing the bill. What are the factors that may change the actual price at runtime? I have listed some of these below:
- Min rate, max rate
- Min qty, max qty
- Min amount, max amount
- Item Class or category
- Externalize during runtime
These other price factors extend the notion of rate x quantity, so we store the extended attributes for any item that needs them. Now we need a processor that can apply the extended item parameters at runtime. Our product, PerpetualInvoice.com is a web application that performs this “magic”. PerpetualInvoice handles this modeling technique through the use of “lists”. The Item List holds the base parameters of rate, quantity and description and a software algorithm applies the extended attributes of the item during runtime. The price changes during runtime can vary from rate changes, usage, price rules, late charges, taxes, you name it, we do it.
If you have a modeling challenge for us please Comment and we will model it for you in PerpetualInvoice! Cloud invoicing is now much easier with PerpetualInvoice.com