A freelancer would be having second thoughts of developing an SME database under a SQL Server Standard edition or above.
Looked up for the standard edition’s license price and it could cost thousands of dollars. I think it is around $3,000.00 – $6,000.00.
I would rather use MYSQL.
Still you can keep using some of the important features of SQL Server. Reporting services is available on express license.
I have hours researching on how to still use and connect Reporting Services to MYSQL under the express license. Creating a linked server connection is the only way for you to connect SSRS express to MYSQL.
If you are planning to use the ODBC connection directly from the report then it will not allow it.
SSRS Express only allows SQL Server connections. So again you have to use linked servers.