Before you hire someone, you need to know what the site is programmed in. Is it PHP (look at the extension on the end of the webpage "blah-blah.com/blah-blah.PHP" means it was programmed in PHP).
It would be also good to know if a free application was used.
Example:
http://www.phorum.org
http://www.simplemachines.net
http://www.phpbb.com
Are all free message boards. All have anti spam modifications (known as 'MODS') that you can insert to do just what you want.
Marc Lesnick
Conference Organizer
Online Dating Convention
Social Networking Event