What payment scheme would be a good choice for my project?

I am trying to figure out a good payment scheme for my project. I am just confused now. :(

This project involved 3 actors.

1. website admin who provide the service/system
2. publisher (who sell space ads)
3. advertiser (who buy space ads)

The payment method will be Paypal only at the moment.

As website admins, we provide a service/application/system where advertisers can buy ads from publisher sand pay them directly using paypal.

We plan to take 10% - 15% of sold ad space. The problem is how can it work?

Example scheme:

Advertiser bought ads from publisher and pays them using paypal. Example price is USD $50.

Is it possible while the advertiser sends the payment to the publisher, it will auto deduct 10% and send the 10% to website admin's paypal account? It sounds impossible with paypal to receive one payment and split it among two recipients automatically.

Possible solutions:

Solution 1.
Once the payment has been received by the publisher, publisher should send the 10% fee to website admin.

Solution 2.
Publisher should pay us directly and we will send the payment to the publisher.

I prefer solution 1 since handling the payment directly from advertisers needs more management.

What do you think? Do you have any solutions for me?

Your scenario is indeed doable with paypal. It's called split or chained payment.

Take a look here: Paypal: Adaptive Payments

I would prefer solution 2.

You will have to keep track of solution 1 for your business to work anyways! If someone isnt paying you will have to get involved. You might as well control the cash and divvy it up. You will also want to track the time frame of the payments. All of this needs to be standardized for you to have a scalable business.

IMHO.