I am confused.  Is your question about the fact that a palm sized computer with 2 possessors, wifi, bluetooth and lots of other stuff takes a lot of power?  Especially when you ad widgets and programs that run and suck power.

Or is your question about a problem with cell service at your house?

If your question is really about using the range extenders, I can say get 1 and give it a try.  Make sure it has the same 30 return policy as the phones in case it does not work.

There is some programs you can download that will show you how much energy is being used.  Turning off Wifi and bluetooth will help.