Costing a website

Okay I had a client visit today to a not for profit company
with regard to doing them a website, I am just curious how
you work out what you should be charging a company for
website you constuct for them? I am sure there are some
contracters and IT managers on my friends list that might
possiably be able to help me work this out at least at the
basic level.

I am not sure anyone here (including myself) knows properly
how to cost a website and i am not sure about what they
are quoting so who can give me a rough guide to how you
would price something like this.

this is only based on design and development including
static html, asp work, database work etc, never had to
worry about this before but i am curious and would be
usefull to know i guess.