A:Answer Hello! The handsets do not have a light indicator for voicemail, however a notification will be displayed on the screen. As for additional handsets, you can add 2 more to this system. There are a few models of handsets that are compatible:
KX-TGEA60
KX-TGEA61
KX-TGFA61B
KX-TGFA71
KX-TGFA85B
KX-TGFA88B
KX-TGFA97
KX-TGFA97B
KX-TGTA61
There is a registration process you have to go through, here you can find the steps: https://help.na.panasonic.com/answers/how-to-register-deregister-a-telephone-handset/ . -M