If you install the server on a computer in your office, you will need a static IP address for your connection. Talk to your ISP about this. They should be able to tell you what your IP number is. A domain name for the IP is not required unless you wish to use SSL.
Depending on their ISP, remote clients who want to connect may also need static IPs. Some ISPs rotate dynamic IPs very frequently (e.g. every 30 minutes). This has the effect of hanging any open connections.
Alternatively, you can install the server on a hosted Virtual Private Server or a colocated server. These always provide static IPs, and will generally provide remote desktop access and a control panel for setting up port forwarding, thus the setup will essentially be the same as for an on-premise server.