The best, simple advice to give someone in this volatile market is to choose a system, phones and infrastructure that run on the current standard (SIP – Session Initiation Protocol). An open system with no licensing fees, hidden away in the fine print.
Big brand VOIP manufacturers are becoming dinosaurs going forward. Selling an XYZ phone system and their proprietary phones is fading fast.
Be able to choose from dozens of manufacturers’ phones, add-ons, etc to build a system. For instance, all these phones will work on the same phone system. $15 to $350 each, you have many choices. Why install a $400 phone for someone in a cubicle that will just be on one line at a time anyway?