The nice thing about
the guide's recommendations on the VoIP end is that they are providers that can scale well into the business end of things. If you go with open standards, you can mix and match providers and software solutions to your heart's content, and there's a lot of excellent sipphone clients and VoIP providers. As for the whole "unlimited" thing, that can be a bit of a trap. Nothing is ever unlimited, and most VoIP providers (even on the business end) define "unlimited" calling for SOHO users as something around the 5000 minutes/month mark with overage billing. What I'm saying is, read the fine print and find out what "unlimited" actually means, because I'll bet you dollars to donuts that it doesn't mean anywhere near the ranges of
200-600+ hours a month that your napkin math might allude to. This is why you need some
real numbers going into this and not just percentages, so I'd highly recommend trying to get some solid usage numbers across the board for everyone involved, both inbound and outbound. Also keep in mind that call forwarding does use outbound minutes from the VoIP provider.
It sounds like a system with virtual server functionality, IVR options, and the ability to set up separate lines would be of use. Before falling down the hole of pre-rolled solutions with nebulous promises of unlimited, price out what you actually need with one of the carriers in the guide, like VOIP.ms. $10 buys you 16 hours, 40 minutes (1000 minutes) of United States talk time (excluding AK/HI) outbound or inbound above the 58 hours, 20 minutes (3500 minutes) of inbound time you can pick up with your DID (your inbound number) for between $5-7 a month. Service wouldn't be difficult to set up and tweak, all the features you'd need would be available, their wiki is full-featured, and you'd have the option of selecting whatever the closest server location(s) they have to you to keep latency low and quality high. Use it as your starting point as you shop around. If others can promise just as good with the option to bring your own high quality softphone equipment (apps like Acrobits, cSipSimple, etc.) so you're not locked into terrible proprietary smartphone apps, then you know you're getting a good deal.
Also, so you are aware as a P'tel customer, this past Monday they launched
two new calling plans. They have an "unlimited" talk and text plan with no data for $20/month, and an "unlimited" talk, text and 2G data plan for $25. Given your potentially changing mobile calling habits, I figured this news might be valuable to know. Hope it all helps, and if you have any other questions, you know where to find me!
One last bit of parting shot advice on this post: I know you all want to be frugal and save money, but reliable communications is clearly an important part of your business. There can be a fine line between frugal and cheap, so be cognizant of that fact. As such,
resist the urge to cut corners for a couple bucks here or there and make call quality, support, reliability and server uptime important deciding factors.
DO NOT BE AFRAID TO SPEND THE MONEY NECESSARY TO GET QUALITY, RELIABLE SERVICE! Got it? Good.