Pay after taking a commission in Paypal?

Hello,

l have a website where Tutors logs in and sell there courses, then Students can buy these courses.

The requirement is to take a commission from each sale for the website owner.

Anyone have used Paypal in a similar scenario ? How a work flow like this will work when using Paypal as a payment method?

Off-topic: I hate Paypal docs soooooo much, Is there a service that give me a Paypal payment method with a good docs?

Thanks,