BE-Excel to Web

Vision - To create financial planning products that enables the customer to quickly implement action and has the ability to measure the results Platform - Program must be Web based. - All technology used must be available on any computer connected to a DSL modem. - Product must run on Internet Explorer and Mozilla. - There should be no proprietary tools that the customer must have on the computer in order for the program to run (eg MS Excel, Access) Flow - Customer will enter information about their income and expenses into various cells. - Program will perform mathematical calculations on the cells (eg add, subtract, multiply) - Program will generate various reports to display the results - Program allows reports to be printed into pdf files OR directly to the customers printer. Database - I need to understand the design difficulty if we allow the customer to store their data on the website. What specific challenges does this present? Perhaps initial version will only allow them to print results.