Custom Service Hosting PHP/Mysql

I need a backend PHP/MySql script for hosting customised services. In simple terms I want to be able to offer about 3 different levels e.g. Bronse, Silver, Gold I want users to be able to select the service they want and pay for it via paypal. In the back end admin panel I want to be able to link each package to a bash script that will run based on variables the user has entered during sign up. backend e.g. Bronse = exec /var/www/scripts/[login to view URL] Bronse answer file location = /var/www/answerfiles Silver = exec /var/www/scripts/[login to view URL] Silver answer file location = /var/www/answerfiles Gold = exec /var/www/scripts/[login to view URL] Gold answer file location = /var/www/answerfiles The back end does not need to be complicated it can even just be a config file I can update myself if that is esier. Users must register prior to ordering and I need some way to be able to view orders. e.g. a password protected page that will list orders in a simple format such as username email package date ordered test address1 Silver 23/06/2010 test2 address2 Gold 29/07/2010 I dont nessisarily need any design work done just a very simple front end that I can adapt after i.e. as long as the buttons work I can link them up to better images and pages later. This is not the inteded purpouse but for example imagine I wanted to sell irc server daemons I would write a bash script that will set up a new instance of the daemon and add the $username $password $max_users variables piped/passed from the php/mysql script into either a custom answer file (see backend e.g. above) that I can tell the script to read or in some other way that you are able to work with? It needs to be scalable so if I want to offer 5 different packages in the future that needs to be possible. I also need to be able to deploy this on multiple servers so documentataion or an installer script is also important. Paypal intergration is a must!. Thanks.