ECS Service Connect usage cost estimation

I am going to use ECS on EC2 for the API architecture that will involve running several Services (e.g. separate adjustable 'container sets'). I need service-to-service communication for them and seems Service Connect feature is most sweet and attractive. How to estimate costs for it properly?

There is no dedicated pricing page (it is not related to Service Discovery, right?). All, I found so far and by understanding the idea, it seems I need to rely on AWS Cloud Map fees 1USD per 1M requests as long as Service Connect uses its namespace. Although according to this 'AmazonECS-developerguide', for Pricing it says "AWS Cloud Map usage is completely free, when Service Connect uses it." and at the same time "Service Connect pricing depends on whether you use AWS Fargate or Amazon EC2 infrastructure". Sounds a bit mysterious for me, searching for help...

P.S. If Cloud Map fees are applied, that means lets assume my 1 (one) end user request will be served by 2-4 services 'jumps' inside my ECS cluster. So I will pay for those internal 'jumps' between my ECS containers, sounds pesky. What is the most native and common solution for service-to-service communication in ECS (I seek for the cheapest one, heh, still wanting to have them as 'Services'. I have seen that it is possible to set 'Links' for containers but it is only inside one single Task Definition, e.g. one Service)