[Can someone explain advance pay to me?]

I got this Cash advance as well. I think it is the double of my monthly average net income over a few months. 

This is the takeaway:

When you receive $100 order, Fiverr will remove:

- 20% normal commission after delivery

- 40% from the $80 you would have collected without a cash advance

NB: In other words you will go home with $40 for every $100 sales during the repayment period.