All data transfer into AWS Database Migration Service is free, and data transferred between AWS Database Migration Service and databases in Amazon RDS and Amazon EC2 Instances in the same Availability Zone also is free. Standard AWS data transfer rates apply when you migrate your source database to a target database in a different Availability Zone, Region, or outside of AWS. Standard AWS data transfer rates are listed on the EC2 instance pricing page.
The cost comes down to the server used and duration it ran, so knowing what size and how long would be of help
Just a quick check for transfer:
The cost comes down to the server used and duration it ran, so knowing what size and how long would be of help
Awesome, I'll do some digging and check it out