VPN on EC2 and static IPs

Software based site-to-site VPN and client-to-site VPN softwares can be deployed on Amazon EC2 to connect to your VPC based resources. Depending on the configuration and application, you may not need static IPs on both sides. For example for client VPN, you can configure Elastic IP (EIP) on your EC2 instance and the users can establish VPN connection using the instance's EIP. If the VPN type is site-to-site there are third party services available by which you can configure VPN using dynamic IPs, but it will depend on your use case. Regarding pricing, for running software based VPN on EC2, you will be charged for EC2 running costs (depending on instance type, tier etc) and there may be associated software charges if you are using a paid version.