Also note, this system works over your NETWORK (not your phone wires). It will connect to up to 4 standard phone lines (or Internet-based VoIP service) but the connection between the phones and the UCM6204 "base" are done over a Ethernet NETWORK. The bad news is that if you only have phone lines running everywhere (2 or 4 wires only) then you will have to run new wiring. The good news is that if you already have a computer network and computers at each phone location, these phones can be connected to that existing network. (If you only have one network jack per location, the phones' built-in network switch lets you "pass" the network connection through the phone to your computer so both can be connected).
Your voicemail greetings give you an excellent opportunity to give your brand a personality and provide you with opportunities to make callers aware of special promotions or new products. The trick, of course, is to get your message across in a clear, concise, and professional manner.

Website: https://smith.ai/blog/28-business-voicemail-greetings-for-main-office-and-personal-numbers-formal-informal-modern-and-just-hilarious
Rehearse or write down your message before recording it. Remember that old saying “practice makes perfect?” It’s certainly true when it comes to creating an electronic greeting. The more you’ve rehearsed, the easier the message will be to restate. If you don’t have time to practice, writing down the greeting before recording it – and then reading it aloud from the paper – may help you stay focused on the correct wording.