Hello & Welcome to Just Answer,
Sorry I didn't see your question earlier and to hear of any issue you are having with your phones.
To help you with this issue, may I ask:
1) The FULL Model Number of the phone system you are working with? If this is a cordless system, that model should be printed on a sticker on the bottom or back of the main base unit and START with a letter or two, and then followed buy a few numbers.
2) When the cordless handsets quit working, did they ALL quit about the same time, or separately?
3) What "features" do you like about these base units make them " extremely convenient" for you?
I ask the questions to see if may be possible to find either some USED components that may work for your situation OR perhaps a NEW system that will meet your needs.
I see it has been a few days and I just wanted to follow up to see if you have any more questions concerning this issue or if the issue was resolved?
I look forward to any further questions or results that you may have.
Thanks, ***** *****--. .-(im)