Regarding auto created VPCs.

This is similar to the question asked here: https://repost.aws/questions/QUgri4pxmGQ66FgrkehfuPgw/does-aws-apply-a-charges-on-default-vpc-which-is-created

A default VPC is created in each region that is enabled for your account. VPCs by themselves have no cost. Resources like Public IPs, and VPC Endpoints may have charges, but these would need to be created to start having a charge. Also Data Transfer can have a charge.