Noobie Freelancer has question about billing

Hi there,

I'm a 5th year student in a design school that has a pretty robust internship program, so I've worked in design firms for probably almost 2 years in total. I'm more focused in motion graphics but have done website comps, and some development.

I've been thinking about freelancing for a while and haven't got around to it until I was approached by a connection through work who has a graphic designer that needs a simple portfolio website.

I need to call and iron out the details, but I think it's going to be a fairly simple (probably 1 page) site just displaying some of her work... I'm not sure if she's going to do the designing or me, and I'll optimize for search engines. Seeing as I'm new to this (as is she, she doesn't have a website at all right now), how much would be a reasonable price to charge (maybe 2 estimates, one with design included and one without)?

Also, is it unusual to just charge a flat rate rather than an hourly one? Just any tips at all are greatly appreciated.