MySQL database developer needed

I run a small two person business that needs to develop a database application to help us manage our commissions receivables, commissions payable, commission advances, sales rep information and customer contract information. This might work fine on MS Access, but I was thinking that open source would be better long term, thus MySQL.

We have been using an ASP application that does not suit all our requirements and believe that we should create our own application. We have done some requirements definitions, that are attached. The screen shots are from the application that we use today, online. It is painfully slow. I don’t anticipate the need to ever have more than one or two people using the application at once.

Of particular importance is the initial architecture stage and understanding all the tables that the database will need, so that our future reporting needed are able to be met. I also would like to know the suggested specs for a server to support the application in house. Could I use a machine that I have available, instead of the latest, in order to save initial costs?