Port Numbers used by SFTP Server and Client

We have the below questions concerning port number.

SFTP Client :
1. Does the SFTP client use any specific port number for connection to SFTP Server ?
2. Can we configure the SFTP client to use a specific port number ?
3. Is it correct that SFTP client only need outgoing port ?

SFTP Server :
4. I understand that the SFTP Server may also use other incoming ports (apart from the one that it will be listening to) so that it can accept connections from multiple clients simultaneously. Can we specify what port numbers the Server should use ?

We need the above information so that we may properly configure firewall equipment to ensure that those ports are not blocked.

Thanks.