Small Winform program to manage computer shop's goods

This should be a small software to manage a computer shop's goods. All items that is buyed from the reseller should be loaded into goods table, and when are sold to its customer should be downloaded from the table. Some additional table to contain data are needed like distibutor, vendor, customer, vat table and so on. Provider should also generate 5 reports should with the visual studio 2005 reporting object to help computer shopper to print its data. The project is based on creation of 10 forms. Forms can be simple, they provide only insert/update/delete functionality, as well as master/detail form where starting, for instance, from a good in stock, shopper should be able to do (in the same form) to open a selling operation, add the item in this transaction, assign a customer, then close the transaction. In the detail now shopper can see to which customer the single goods has been sold, when and detail of the good. May be some forms can be added according to some point we can further discuss along the way. All forms should provide a search functionality to allow computer shopper to easy find data. Solution should be provided in this way: - Winform project with data insert check constraints. Some constaints has been placed on the SQL Express 2005 db, other must be implemented by the provider. - c# 2.0 code with full source code released - 3 tier infrastructure built in separate dll, data should pass between the DataLayer dll and the ObjectDataSource .net provider, so a future database switch can be done without problems. - use only .net 2005 components. On your side the payment will be done via escrow so you can be sure to get your money when the works end. Attached there is the db structure (SQL 2005 express) that should be used to create the project. That is just the structure, no trigger as well as no constraints has been created except the relationship. Project it's a very small project.