As long as you have a stable internet connection, a static IP address for the server, a separate FMP or FMPA license on each computer, you can connect to the server from home using a remote internet connection. The server must remain on (no sleep mode) and have FM running with the File>Share>FileMaker Network… turned on. Port 5003 on the server's router must be forwarded to the server (see this article: http://portforward.com/english/routers/port_forwarding/Apple/AirPortExtreme/FileMaker_Pro_Advanced_12.htm).
The server can use FMP, FMPA, FMS or FMSA. FMS and FMSA are more robust and offer services like automatic backups. FMP and FMPA support up to 9 clients; FMS 250; FMSA unlimited.
If you use iPads instead of Macs as clients, then you can use FM Go which is free instead of another FMP license.
Perfect answer! Thank you