Thats a big ask for your first.

Im not sure what a PHP Nuke magazine is?

And for the forum, is there no shortcuts like just buying a vB license? I can't see the point in coding a forum unless your talking top end bespoke client, lots of time gone wasted really.

As for the price, for me it depends on the turnaround hes expected. If its short i'd go high price, however if its a side project with a slow turnaround then a more reasonable price. So whats the turnaround hes expecting?

If your not sure on how to quote him. Why not put the ball in his court, and ask for his budget. If you think you can do that work in the time, up to your own standards then go for it. Otherwise, uncheck a few boxes on the list and he can up his price for the things that you feel are worth more?