A solution is: when you call your home, don't call the GV#.

Instead, call the SipGate or IpKall # that's registered or forwarded to your ATA. Then if nobody's home to pick up the call, you're not charged.

You may get an ipkall # just for this purpose.

You may also give these "internal" (secrete) numbers to your close friends and relatives, but never give them to banks!