Out of curiosity and because I don't want to create a test account right now:

How does billing with "Deploy on AWS" work? Do I need to bring my own AWS account and Polars is payed for the image through AWS or am I billed by Polars and they pass a share to AWS. In other words do I have a contract primarily with AWS or Polars?

Your billing partner is AWS. Polars' markup is on your AWS bill.