For quads and others I just picked up a new cordless phone. It is called the Serene CL-35. Big buttons and most importantly a very good speakerphone allowing you to keep it in your lap and not strain your hands and shoulders holding it up. You can velcro a plastic phone handle (available from Sammons) on the back to make it easier to pick up and hold.

You can purchase the phone through hearmore.com

http://www.hearmore.com/store/prodVi...ss-Phone:-38dB