Hi @AzureLearnings81 , As previously stated, there is no immediate cost for Data Sync but there are costs associated. See: How much does the SQL Data Sync service cost
There's no charge for the SQL Data Sync service itself. However, you still collect data transfer charges for data movement in and out of your SQL Database instance. For more info, see SQL Database pricing.
Additionally, sometimes I encounter 3rd party documentation that segues nicely into the Microsoft documentation, and one of those is this: Azure SQL Data Sync Limitations Pricing And Alternatives
It does fail to convey the free aspect of the Data Sync service but that is covered above. What it does is spell out the detail in a nice, clean format and then goes on to reference the official documentation. The Data Sync overview document is very thorough, and should be refenced but the Gigxp.com page offers alternatives, too.