If you have never used VoIP, there are two basic ways to go – either gradually in phases, or completely on a wholesale switchover. In your case, the former would be best, and you can painlessly trial VoIP on a small scale and gauge the savings for yourself. One way would be to VoIP-enable a branch office and use it as a test case. Or you could just get a couple of VoIP lines to trial on their own.
Most VoIP services do not involve contracts, so if it doesn't prove worthwhile, you can easily drop the service. I should also add that trialing a few VoIP lines can easily be done on your own, without the involvement or expense of bringing in an IT consultant. You will need their services if you decide to deploy VoIP on a larger scale, but for now, a simple trial should be sufficient.
This was first published in January 2009