Look, there are a couple of things you have to know before hiring a coder:
1. Pay after the hack has been installed and thoroughly tested on your forum. He requests money up front? Don't give into that crap! There are many coders that accept money after the hack has been completed, installed, and tested for about a week.
2. Buy from someone reputable. Does the person you are hiring have a website which lists their clients and what they have done? Do they have a resume of some sort?
3. Consider your price range. Do you have plenty of money overflowing your pockets? In that case, I'd probably consider the vbMechanic (
www.vbmechanic.com), where you will get a professional job done. His job is making professional vBulletin hacks!
Hope that helps!