How do I charge for this type of photography session?

I have been approached by a director for a leading cosmetics company who is interested in having me photograph an event where clients will be receiving makeovers and I will be taking the before and after photos. I'm just starting out and have never done anything like this so I don't know how to charge them. I was thinking that I would charge either a sitting fee per person or an hourly rate while offering portrait packages to the ladies receiving the makeovers. Would it be fair to offer a percentage of the portrait package sales back to the director since I would have never made the sales if it weren't for her? If so, what percentage? Does anyone have a better idea?

Thanks in advance!!

Charge by the hour. Don't offer portrait packages. Don't solicit for other work while you're working. Simply hand out a business card. If they like your work they'll call you. Charge $125 per hour. That's pretty much what it's worth. Don't charge that if you're just sitting there and chatting with someone. You should be working the entire time. That's what I've charged for commercial and people love it. Ask if you can deliver the prints on a CD or DVD. If you have to deliver high resolution 8X10s then the charge would be additional per print.
Hope that helps.

Charge $350 for a 4 hour shoot with rights to use the resulting photographs at the current per use fee (this depends upon a number of things ... Internet usage, point of sale photographs, "complimentary" photos to the participants, up to and including national ads)

Each usage fee is different.

Make sure your image files include your copyright notice on each file with "All rights reserved" included in the notice.

You know of course how to do this using Bridge to append your XMP files with copyright notice, your contact information, the clients contact information and key words.

I am very big on ethics in business. I always avoid giving or offering kickbacks. This will only hurt you in the long run. People in our type of business will get a reputation and it will only work against you.

I would assume that since this cosmetic company is having you take pictures of their clients I would assume it is for the company benefit
So what to you charge? Well the answer can not be determined from what you have presented. Price is determined by how the company intends to use the pictures. If they intend to use it for their promotion in ads then you would charge more than if they just want to use it in a flyer.
So first step is just to ask what is the end product. Is it an Ad? Is it for the client? Is it for a brouchure?
Generally speaking I ask for a Photo rate. (some people call this a day rate) I NEVER ask for a day rate. This is because one of two things will happen.
Lets say my day rate is 2000 per day. The first thing they will say Is I only need you for 4 hours so we only have to pay you 1000.
Or
You work all day and all of a sudden 20 shots are added and you end up working 18 hours.

Now since you are new it is logical to think that they want these pics for documentation. If that is the case I think 400 Photo Fee is reasonable. This will give you negotiating room if they are the type to say any Fee is too high.. Some people if you said 100 Dollars they still would try to get it for half. Now if they request special lighting or other expenses that can be charged as expenses on top of the fee. Just make sure you clarify that in advance and keep all recipients.

If you go to APA s website there are pricing guidelines if the picture are more than just documentation

http://www.apanational.com/

Lots of sound advise here. Here is also a great software
http://www.fotoquote.com/