83129 Web Mail (CGI & flat file) Mod

I'm about to use a web mail package from http://www.webumake.com. It has many features and is a rather simple program: CGI/PERL scripts for the engine and using a flat file database. Most of the configuration files are simple text files. The configuration file for the various user features (can they get POP mail, forward incoming mail to POP address, allotted disk space, etc) is a nice CGI interface program written out to a text file. The configuration file is for all e-mail users. I need someone to separate my users into 2 groups: Paying/NonPaying. This would either be added to the existing CGI interface or given its on interface. If a user is a paid member they would be given access to more features than the non-paying members. I don't need any new features created; I just want to assign the existing features based on Paying or Non-Paying customers. There are many PayPal scripts out there, but I would like one customized/created so that a non-paying user could click a link and "upgrade" to the $20 per year account and automatically get the new features. My site is running on a Windows 2000 server and is not available to the public for use. You will be able to test it thoroughly. I have several other projects that I would like done after this is complete. I'm looking for a programmer who will familiarize themselves with my operation and continue to make upgrades/changes as necessary. Speed is nice... but proficiency is a MUST.