It's 20% of the first $500 with a client, not by project. So, if it's your first project with a client and the price is $300, you will pay 20%, or $60. But, if you've had other contracts with the client in the past that totalled more than $500 and now you start a new contract that is $300, you will pay 10%, or $30.
I see Tiffany and Preston already responded to your question. Please note that in order to participate in the Community, you need to create your profile and get an approval from our team.